50278 + Interview Questions in Physics

1.	A man grows into a giant such that his linear dimensions increase by a factor of 9. Assuming that his density remains same, the stress in the leg will change by a factor of
Answer» A man grows into a giant such that his linear dimensions increase by a factor of $9$ . Assuming that his density remains same, the stress in the leg will change by a factor of

Discussion

2.	A particle start from rest, accelerates at 2m/s² for 10s and then goes for constant speed for 30s and decelaratd s at 4m/s² till it stops after next .what is the distance c travelled by it?
Answer» A particle start from rest, accelerates at 2m/s² for 10s and then goes for constant speed for 30s and decelaratd s at 4m/s² till it stops after next .what is the distance c travelled by it?

Discussion

3.	A rectangular lamina is shown in the figure below. Find the radius of gyration about the axis passing through its COM, perpendicular to the plane of the rectangular lamina. [in metres]
Answer» A rectangular lamina is shown in the figure below. Find the radius of gyration about the axis passing through its COM, perpendicular to the plane of the rectangular lamina. [in $metres$ ]

Discussion

4.	A voltmeter of resistance 400 Ω is used to measure the potential difference across the 100 Ω resistor in the circuit shown in figure (32-E24). (a) What will be the reading of the voltmeter? (b) What was the potential difference across 100 Omega before the voltmeter was connected ?
Answer» A voltmeter of resistance 400 $Ω$ is used to measure the potential difference across the 100 $Ω$ resistor in the circuit shown in figure (32-E24). (a) What will be the reading of the voltmeter? (b) What was the potential difference across 100 $O m e g a$ before the voltmeter was connected ?

4.

A voltmeter of resistance 400 Ω is used to measure the potential difference across the 100 Ω resistor in the circuit shown in figure (32-E24). (a) What will be the reading of the voltmeter? (b) What was the potential difference across 100 Omega before the voltmeter was connected ?

Answer»

A voltmeter of resistance 400 $Ω$ is used to measure the potential difference across the 100 $Ω$ resistor in the circuit shown in figure (32-E24). (a) What will be the reading of the voltmeter? (b) What was the potential difference across 100 $O m e g a$ before the voltmeter was connected ?

Discussion

5.	When a planet orbiting around the sun an elliptical orbit R1 and R2 are the closest and farthest distance from the sun Then the ratio of the magnitudes of maximum and minimum gravitational forces between them is A.r1:r2 B.r2:r1 C.r1^2:r2^2 D.r2^2:r1^2
Answer» When a planet orbiting around the sun an elliptical orbit R1 and R2 are the closest and farthest distance from the sun Then the ratio of the magnitudes of maximum and minimum gravitational forces between them is A.r1:r2 B.r2:r1 C.r1^2:r2^2 D.r2^2:r1^2

5.

When a planet orbiting around the sun an elliptical orbit R1 and R2 are the closest and farthest distance from the sun Then the ratio of the magnitudes of maximum and minimum gravitational forces between them is A.r1:r2 B.r2:r1 C.r1^2:r2^2 D.r2^2:r1^2

Answer»

When a planet orbiting around the sun an elliptical orbit R1 and R2 are the closest and farthest distance from the sun Then the ratio of the magnitudes of maximum and minimum gravitational forces between them is

A.r1:r2

B.r2:r1

C.r1^2:r2^2

D.r2^2:r1^2

Discussion

6.	A harmonic wave is travelling on string 1. At the junction with string 2, it is partly reflected and partly transmitted. The linear mass density of string 2 is 9 times that of string 1, and that the boundary between the two strings is at x=0. If the expression for the incident wave is yi=(3 cm)cos[(3.14 cm−1)x−(314 rad s−1)t]. What is the expression for the transmitted waves?
Answer» A harmonic wave is travelling on string $1$ . At the junction with string $2$ , it is partly reflected and partly transmitted. The linear mass density of string $2$ is $9$ times that of string $1$ , and that the boundary between the two strings is at $x = 0$ . If the expression for the incident wave is $y_{i} = (3 cm) cos [(3.14 {cm}^{- 1}) x - (314 {rad s}^{- 1}) t]$ . What is the expression for the transmitted waves?

Discussion

7.	A car of 1000 kg, is accelerating due to a net force 1200 N. If 4 people of mass 50 Kg board the car, then what is the new acceleration? (in ms2) ___
Answer» A car of 1000 kg, is accelerating due to a net force 1200 N. If 4 people of mass 50 Kg board the car, then what is the new acceleration? (in $\frac{m}{s^{2}})$ ___

7.

A car of 1000 kg, is accelerating due to a net force 1200 N. If 4 people of mass 50 Kg board the car, then what is the new acceleration? (in ms2) ___

Answer»

A car of 1000 kg, is accelerating due to a net force 1200 N. If 4 people of mass 50 Kg board the car, then what is the new acceleration? (in $\frac{m}{s^{2}})$

___

Discussion

8.	The electric potential inside a charged sphere varies with the distance 'r' from its centre as V = a - br3, where 'a' and 'b' are positive constant. Then select the correct statement(s) from the following. (where E = Electric field inside the sphere at a distance ‘r’ from its centre, ρ = volume charge density inside the sphere at a distance ‘r’ from its centre)
Answer» The electric potential inside a charged sphere varies with the distance 'r' from its centre as V = a - br $^{3}$ , where 'a' and 'b' are positive constant. Then select the correct statement(s) from the following. (where E = Electric field inside the sphere at a distance ‘r’ from its centre, $ρ$ = volume charge density inside the sphere at a distance ‘r’ from its centre)

8.

The electric potential inside a charged sphere varies with the distance 'r' from its centre as V = a - br3, where 'a' and 'b' are positive constant. Then select the correct statement(s) from the following. (where E = Electric field inside the sphere at a distance ‘r’ from its centre, ρ = volume charge density inside the sphere at a distance ‘r’ from its centre)

Answer»

The electric potential inside a charged sphere varies with the distance 'r' from its centre as V = a - br $^{3}$ , where 'a' and 'b' are positive constant. Then select the correct statement(s) from the following.

(where E = Electric field inside the sphere at a distance ‘r’ from its centre, $ρ$ = volume charge density inside the sphere at a distance ‘r’ from its centre)

Discussion

9.	Name the gate represented by the following circuit.
Answer» Name the gate represented by the following circuit.

Discussion

10.	Two identical spheres are placed in contact with each other. The force of gravitation between the spheres will be proportional to (R = radius of each sphere)
Answer» Two identical spheres are placed in contact with each other. The force of gravitation between the spheres will be proportional to (R = radius of each sphere)

Discussion

11.	A block of mass 'm' is initially lying on a wedge of mass 'M' with an angle of inclination θ, as shown in the figure. Calculate the displacement of the wedge when the block reaches bottom of the wedge.
Answer» A block of mass 'm' is initially lying on a wedge of mass 'M' with an angle of inclination $θ$ , as shown in the figure. Calculate the displacement of the wedge when the block reaches bottom of the wedge.

Discussion

12.	A metallic sphere of radius r and specific heat S is rotated about an axis passing through its centre of mass at an angular speed of n rotations per second. It is suddenly stopped and 50% of its energy is used in increasing its temperature. Then, the rise in temperature of the sphere is
Answer» A metallic sphere of radius $r$ and specific heat $S$ is rotated about an axis passing through its centre of mass at an angular speed of $n$ rotations per second. It is suddenly stopped and $50 %$ of its energy is used in increasing its temperature. Then, the rise in temperature of the sphere is

Discussion

13.	A body initially at 80∘C cools to 64∘C in 5 minutes and to 52∘C after another 5 minutes. The temperature of the surroundings is
Answer» A body initially at $80^{\circ} C$ cools to $64^{\circ} C$ in $5$ minutes and to $52^{\circ} C$ after another $5$ minutes. The temperature of the surroundings is

Discussion

14.	A mass of M kg is suspended by a weightless string. The horizontal force required to displace it until the string makes an angel of 45∘ with the initial vertical direction is
Answer» A mass of M kg is suspended by a weightless string. The horizontal force required to displace it until the string makes an angel of $45^{\circ}$ with the initial vertical direction is

Discussion

15.	A thin spherical shell having uniform density is cut in two parts by a plane and kept separated as shown in figure (11-E3). The point A is the centre of the plane section of the first part and B is the centre of the plane section of the second part. Show that the gravitational field at A due to the first part is equal in magnitude t the gravitrational field at B due to the second part.
Answer» A thin spherical shell having uniform density is cut in two parts by a plane and kept separated as shown in figure (11-E3). The point A is the centre of the plane section of the first part and B is the centre of the plane section of the second part. Show that the gravitational field at A due to the first part is equal in magnitude t the gravitrational field at B due to the second part.

Discussion

16.	A man has a weight 105 N on a weighing machine kept near the north pole of the earth. What will be the reduction in the weight of the man if he moves to the equator? Take g=9.8 m/s2, radius of earth (R)=6400 km, angular speed of the earth ω=7.27×10−5 rad/s.
Answer» A man has a weight $105 N$ on a weighing machine kept near the north pole of the earth. What will be the reduction in the weight of the man if he moves to the equator? Take $g = 9.8 {m/s}^{2}$ , radius of earth ( $R) = 6400 km$ , angular speed of the earth $ω = 7.27 \times 10^{- 5} rad/s$ .

Discussion

17.	The angular velocity of a body changes from ω1 to ω2 without applying a torque but changing moment of inertia. The ratio of corresponding radii of gyration
Answer» The angular velocity of a body changes from $ω_{1}$ to $ω_{2}$ without applying a torque but changing moment of inertia. The ratio of corresponding radii of gyration

17.

The angular velocity of a body changes from ω1 to ω2 without applying a torque but changing moment of inertia. The ratio of corresponding radii of gyration

Answer»

The angular velocity of a body changes from $ω_{1}$ to $ω_{2}$ without applying a torque but changing moment of inertia. The ratio of corresponding radii of gyration

Discussion

18.	When a charged particle enters a magnetic field in a direction perpendicular to the field, which one of the following does not change?
Answer» When a charged particle enters a magnetic field in a direction perpendicular to the field, which one of the following does not change?

Discussion

19.	A fixed horizontal wire A carrying current of 8 A supports another horizontal wire B carrying current 10 A , hanging in air at a distance 5 cm below the wire A. Considering the direction of current in two wires as same. Find the weight of wire B.
Answer» A fixed horizontal wire A carrying current of 8 A supports another horizontal wire B carrying current 10 A , hanging in air at a distance 5 cm below the wire A. Considering the direction of current in two wires as same. Find the weight of wire B.

Discussion

20.	If a train travelling at 30 m/s is to be brought to rest in a distance of 200 m, then its retardation should be
Answer» If a train travelling at $30 m/s$ is to be brought to rest in a distance of $200 m$ , then its retardation should be

Discussion

21.	relationship is called
Answer» relationship is called

Discussion

22.	A square plate of edge ′a2′ is cut from a uniform square plate of edge 'a' as shown in figure. Mass of square plate of edge 'a' is M. Find out the moment of inertia of the remaining square plate about an axis passing through 'O' (center of square plate of side 'a') and perpendicular to the plane of the plate.
Answer» A square plate of edge ${\frac{^{'} a}{2}}^{'}$ is cut from a uniform square plate of edge 'a' as shown in figure. Mass of square plate of edge 'a' is $M$ . Find out the moment of inertia of the remaining square plate about an axis passing through 'O' (center of square plate of side 'a') and perpendicular to the plane of the plate.

Discussion

23.	In order to increase the resistance of a given wire of uniform cross section to four times its value, a fraction of its length is stretched uniformly till the full length of the wire becomes 32 times the original length. If the fraction of wire that is streched is found to be n16. Then the value of n is ?
Answer» In order to increase the resistance of a given wire of uniform cross section to four times its value, a fraction of its length is stretched uniformly till the full length of the wire becomes $\frac{3}{2}$ times the original length. If the fraction of wire that is streched is found to be $\frac{n}{16}$ . Then the value of $n$ is ?

Discussion

24.	The figure illustrates plane figures made of thin conductors which are located in a uniform magnetic field directed away from the reader, perpendicular to the plane of drawing. The magnetic field starts decreasing. The currents induced in these loops are directed as
Answer» The figure illustrates plane figures made of thin conductors which are located in a uniform magnetic field directed away from the reader, perpendicular to the plane of drawing. The magnetic field starts decreasing. The currents induced in these loops are directed as

Discussion

25.	If a rubber ball is taken at the depth of 200 m in a pool its volume decreases by 0.2%. If the density of the water is 103 kg/m3 and g=10 m/s2, then the volume elasticity in N/m2 will be:
Answer» If a rubber ball is taken at the depth of 200 m in a pool its volume decreases by 0.2%. If the density of the water is $10^{3} k g / m^{3}$ and $g = 10 m / s^{2}$ , then the volume elasticity in $N / m^{2}$ will be:

Discussion

26.	Above graph shows stopping potential versus 1wavelength for three metals, then
Answer» Above graph shows stopping potential versus $\frac{1}{wavelength}$ for three metals, then

26.

Above graph shows stopping potential versus 1wavelength for three metals, then

Answer»

Above graph shows stopping potential versus $\frac{1}{wavelength}$ for three metals, then

Discussion

27.	A particle of mass m moves along the quarter section of the circular path whose centre is at the origin. The radius of the circular path is a. A force →F=y^i−x^j N acts on the particle, where x,y denote the coordinates of position of the particle. Calculate the work done by this force, if the particle displaces from point A(a,0) to point B(0,a) along the circular path.
Answer» A particle of mass $m$ moves along the quarter section of the circular path whose centre is at the origin. The radius of the circular path is $a$ . A force $\to F = y^i - x^j N$ acts on the particle, where $x, y$ denote the coordinates of position of the particle. Calculate the work done by this force, if the particle displaces from point $A (a, 0)$ to point $B (0, a)$ along the circular path.

Discussion

28.	The blocks (m2>m1) are held in such a manner that spring is unstretched initially. Consider the situation at the time of release of the block (t=0) and short time after releasing the block (t>0). Accelerations of the blocks of masses m1 and m2 are a1 and a2 respectively
Answer» The blocks $(m_{2} > m_{1})$ are held in such a manner that spring is unstretched initially. Consider the situation at the time of release of the block $(t = 0)$ and short time after releasing the block $(t > 0)$ . Accelerations of the blocks of masses $m_{1}$ and $m_{2}$ are $a_{1}$ and $a_{2}$ respectively

Discussion

29.	An 8m long copper wire and a 4m long steel wire, each of cross-section 0.5 cm2 are fastened end to end and stretched by a 500 N force. The elastic potential energy of the system is (YCopper=1×1011Nm−2;Ysteel=2×1011Nm−2)
Answer» An 8m long copper wire and a 4m long steel wire, each of cross-section 0.5 cm² are fastened end to end and stretched by a 500 N force. The elastic potential energy of the system is $(Y_{C o p p e r} = 1 \times 10^{11} N m^{- 2}; Y_{s t e e l} = 2 \times 10^{11} N m^{- 2})$

Discussion

30.	A mirror in the first quadrant is in the shape of a hyperbola whose equation is xy=1. A light source in the second quadrant emits a beam of light that hits the mirror at the point (2,12). If the reflected ray is parallel to the y−axis, the slope of the incident beam is
Answer» A mirror in the first quadrant is in the shape of a hyperbola whose equation is $x y = 1.$ A light source in the second quadrant emits a beam of light that hits the mirror at the point $(2, \frac{1}{2}) .$ If the reflected ray is parallel to the $y -$ axis, the slope of the incident beam is

Discussion

31.	Two pendula start swinging simultaneously. By the time first pendulum makes 20 oscillations, 2nd pendulum makes 15 oscillations. The ratio of their lengths is
Answer» Two pendula start swinging simultaneously. By the time first pendulum makes 20 oscillations, $2^{n} d$ pendulum makes 15 oscillations. The ratio of their lengths is

Discussion

32.	The vertical component of earth's magnetic field is zero at or The earth's magnetic field always has a vertical component except at the
Answer» The vertical component of earth's magnetic field is zero at or The earth's magnetic field always has a vertical component except at the

Discussion

33.	A cord is used to lower vertically a block of mass M by a distance d with constant downward acceleration g4 . Work done by the cord on the block is
Answer» A cord is used to lower vertically a block of mass M by a distance d with constant downward acceleration $\frac{g}{4}$ . Work done by the cord on the block is

33.

A cord is used to lower vertically a block of mass M by a distance d with constant downward acceleration g4 . Work done by the cord on the block is

Answer»

A cord is used to lower vertically a block of mass M by a distance d with constant downward acceleration $\frac{g}{4}$ . Work done by the cord on the block is

Discussion

34.	In a rigid wire frame ABCDEFA, as shown in the figure, a current I0 flows through the wire from A to F as shown in the figure. Radii of the three quarters, AB, CD and EF are r1=314=314m and r3=1m respectively with common center at O. All the wires are light except for the portion ED which have a mass of ‘m’ kg. The magnetic moment of the loop is
Answer» In a rigid wire frame ABCDEFA, as shown in the figure, a current I0 flows through the wire from A to F as shown in the figure. Radii of the three quarters, AB, CD and EF are $r_{1} = 3^{\frac{1}{4}} = 3^{\frac{1}{4}} m$ and $r_{3} = 1 m$ respectively with common center at O. All the wires are light except for the portion ED which have a mass of ‘m’ kg. The magnetic moment of the loop is

34.

In a rigid wire frame ABCDEFA, as shown in the figure, a current I0 flows through the wire from A to F as shown in the figure. Radii of the three quarters, AB, CD and EF are r1=314=314m and r3=1m respectively with common center at O. All the wires are light except for the portion ED which have a mass of ‘m’ kg. The magnetic moment of the loop is

Answer»

In a rigid wire frame ABCDEFA, as shown in the figure, a current I0 flows through the wire from A to F as shown in the figure. Radii of the three quarters, AB, CD and EF are $r_{1} = 3^{\frac{1}{4}} = 3^{\frac{1}{4}} m$ and $r_{3} = 1 m$ respectively with common center at O. All the wires are light except for the portion ED which have a mass of ‘m’ kg.

The magnetic moment of the loop is

Discussion

35.	A tuning fork (pair) produces 4 beats/sec with another fork of frequency 288 Hz. A little wax is placed on the unknown fork and it then produces 2 beats/sec. The frequency of the unknown fork is
Answer» A tuning fork (pair) produces 4 beats/sec with another fork of frequency 288 Hz. A little wax is placed on the unknown fork and it then produces 2 beats/sec. The frequency of the unknown fork is

Discussion

36.	A plate of mass M is placed on a horizontal frictionless surface (see figure) and a body of mass m is placed on this plate. The coefficient of dynamics friction between this body and the plate is μ. If a force 2 μmg is applied to the body of mass m along the horizontal, the acceleration of the plate will be
Answer» A plate of mass M is placed on a horizontal frictionless surface (see figure) and a body of mass m is placed on this plate. The coefficient of dynamics friction between this body and the plate is μ. If a force 2 μmg is applied to the body of mass m along the horizontal, the acceleration of the plate will be

36.

A plate of mass M is placed on a horizontal frictionless surface (see figure) and a body of mass m is placed on this plate. The coefficient of dynamics friction between this body and the plate is μ. If a force 2 μmg is applied to the body of mass m along the horizontal, the acceleration of the plate will be

Answer»

A plate of mass M is placed on a horizontal frictionless surface (see figure) and a body of mass m is placed on this plate. The coefficient of dynamics friction between this body and the plate is μ. If a force 2 μmg is applied to the body of mass m along the horizontal, the acceleration of the plate will be

Discussion

37.	Two blocks of mass m and 2m are connected as shown in figure. A force F is acting on the block of mass 4m. Pulley is massless and string is light and inextensible. All the surfaces are smooth. Contact force between ground and the 4m mass under the previous problem condition is
Answer» Two blocks of mass m and 2m are connected as shown in figure. A force F is acting on the block of mass 4m. Pulley is massless and string is light and inextensible. All the surfaces are smooth. Contact force between ground and the 4m mass under the previous problem condition is

37.

Two blocks of mass m and 2m are connected as shown in figure. A force F is acting on the block of mass 4m. Pulley is massless and string is light and inextensible. All the surfaces are smooth. Contact force between ground and the 4m mass under the previous problem condition is

Answer»

Two blocks of mass m and 2m are connected as shown in figure. A force F is acting on the block of mass 4m. Pulley is massless and string is light and inextensible. All the surfaces are smooth.

Contact force between ground and the 4m mass under the previous problem condition is

Discussion

38.	Following figure shows different combinations of identical bulbs connected to identical battery(ies). Which option is correct regarding the total power dissipated in the circuit?
Answer» Following figure shows different combinations of identical bulbs connected to identical battery(ies). Which option is correct regarding the total power dissipated in the circuit?

38.

Following figure shows different combinations of identical bulbs connected to identical battery(ies). Which option is correct regarding the total power dissipated in the circuit?

Answer»

Following figure shows different combinations of identical bulbs connected to identical battery(ies). Which option is correct regarding the total power dissipated in the circuit?

Discussion

39.	In Young's double slit experiment, the distance of the nth dark fringe from the centre is-
Answer» In Young's double slit experiment, the distance of the $n^{t h}$ dark fringe from the centre is-

Discussion

40.	A particle at a height 'h' from the ground is projected with an angle 30∘ from the horizontal. It strikes the ground making angles 45∘ with horizontal. It is again projected from the same point with the same speed but with an angle of 60∘ with horizontal. Find the angle it makes with the horizontal when it strikes the ground.
Answer» A particle at a height ' $h$ ' from the ground is projected with an angle $30^{\circ}$ from the horizontal. It strikes the ground making angles $45^{\circ}$ with horizontal. It is again projected from the same point with the same speed but with an angle of $60^{\circ}$ with horizontal. Find the angle it makes with the horizontal when it strikes the ground.

Discussion

41.	What are the applications of elasticity?
Answer» What are the applications of elasticity?

Discussion

42.	In the arrangement shown in figure. There is a fricion force between the block of masses m and 2m. Block of mass 2m is kept on a smooth horizontal plane. The mass of suspended block is m. Block A is stationary with respect to block of mass 2m. The minimum value of coefficient of fricion betwen A and B is
Answer» In the arrangement shown in figure. There is a fricion force between the block of masses $m$ and $2 m$ . Block of mass $2 m$ is kept on a smooth horizontal plane. The mass of suspended block is $m$ . Block $A$ is stationary with respect to block of mass $2 m$ . The minimum value of coefficient of fricion betwen $A$ and $B$ is

Discussion

43.	Particles of masses 1 g, 2 g, 3 g, ......, 100 g are kept at the marks 1 cm, 2 cm, 3 cm, ......., 100 cm respectively on metre scale. Find the moment of inertia of the system of particles about a perpendicular bisector of the metre scale.
Answer» Particles of masses 1 g, 2 g, 3 g, ......, 100 g are kept at the marks 1 cm, 2 cm, 3 cm, ......., 100 cm respectively on metre scale. Find the moment of inertia of the system of particles about a perpendicular bisector of the metre scale.

Discussion

44.	Seven homogeneous bricks,each of length L, are arranged as shown in figure (9-E2).Each brick is displaced with respect to the one in contact by L/10.Find the x-coordinate of the centre of mass relative to the origin shown.
Answer» Seven homogeneous bricks,each of length L, are arranged as shown in figure (9-E2).Each brick is displaced with respect to the one in contact by L/10.Find the x-coordinate of the centre of mass relative to the origin shown.

44.

Seven homogeneous bricks,each of length L, are arranged as shown in figure (9-E2).Each brick is displaced with respect to the one in contact by L/10.Find the x-coordinate of the centre of mass relative to the origin shown.

Answer»

Seven homogeneous bricks,each of length L, are arranged as shown in figure (9-E2).Each brick is displaced with respect to the one in contact by L/10.Find the x-coordinate of the centre of mass relative to the origin shown.

Discussion

45.	A pilot takes off from an airport at 15∘S latitude and flies 55∘ due North. What latitude has the pilot reached?
Answer» A pilot takes off from an airport at 15 $^{\circ}$ S latitude and flies 55 $^{\circ}$ due North. What latitude has the pilot reached?

Discussion

46.	The point from where a ball of mass 2 kg is projected is taken as the origin of the co-ordinate axes. The x and y components of its displacement are given by x=6t and y=8t−5t2. Find the impulse ( in kg m/s) acting on it between the time t=0 to t=2 seconds
Answer» The point from where a ball of mass $2 kg$ is projected is taken as the origin of the co-ordinate axes. The $x$ and $y$ components of its displacement are given by $x = 6 t$ and $y = 8 t - 5 t^{2}$ . Find the impulse ( in $kg m/s$ ) acting on it between the time $t = 0$ to $t = 2$ seconds

Discussion

47.	In the circuit shown, X is joined to Y for a long time, and then X is joined to Z. The total heat produced in R2 is
Answer» In the circuit shown, X is joined to Y for a long time, and then X is joined to Z. The total heat produced in $R_{2}$ is

Discussion

48.	A T shaped object with dimensions shown in the figure is lying on a smooth floor. A force →F is applied at the point P parallel to AB such that the object has only the translational motion without rotation. Find the location of P with respect to C.
Answer» A T shaped object with dimensions shown in the figure is lying on a smooth floor. A force $\to F$ is applied at the point P parallel to AB such that the object has only the translational motion without rotation. Find the location of P with respect to C.

Discussion

49.	Water is filled in a uniform container of area of cross section A. A hole of cross section area a (
Answer» Water is filled in a uniform container of area of cross section A. A hole of cross section area a (<< A) is made in the container at a height of 20 m above the base. Water streams out and hits a small block placed at some distance from container. With what speed $(i n m s^{- 1})$ the block should be moved such that water streams always hits the block. (Given $\frac{a}{A} = \frac{1}{20}$ ). (Take $g = 10 m s^{- 2}$ ) ___

Discussion

50.	Three smooth pulleys are connected by a light string. A mass m is attached to the pulley P3. Assume the strings between two pulleys and between the pulley and the support to be vertical. If all the pulleys are massless then the tension in the string over the pulleys is
Answer» Three smooth pulleys are connected by a light string. A mass m is attached to the pulley $P_{3}$ . Assume the strings between two pulleys and between the pulley and the support to be vertical. If all the pulleys are massless then the tension in the string over the pulleys is

50.

Three smooth pulleys are connected by a light string. A mass m is attached to the pulley P3. Assume the strings between two pulleys and between the pulley and the support to be vertical. If all the pulleys are massless then the tension in the string over the pulleys is

Answer»

Three smooth pulleys are connected by a light string. A mass m is attached to the pulley $P_{3}$ . Assume the strings between two pulleys and between the pulley and the support to be vertical. If all the pulleys are massless then the tension in the string over the pulleys is

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A man grows into a giant such that his linear dimensions increase by a factor of 9. Assuming that his density remains same, the stress in the leg will change by a factor of

A particle start from rest, accelerates at 2m/s² for 10s and then goes for constant speed for 30s and decelaratd s at 4m/s² till it stops after next .what is the distance c travelled by it?

A rectangular lamina is shown in the figure below. Find the radius of gyration about the axis passing through its COM, perpendicular to the plane of the rectangular lamina. [in metres]

A voltmeter of resistance 400 Ω is used to measure the potential difference across the 100 Ω resistor in the circuit shown in figure (32-E24). (a) What will be the reading of the voltmeter? (b) What was the potential difference across 100 Omega before the voltmeter was connected ?

When a planet orbiting around the sun an elliptical orbit R1 and R2 are the closest and farthest distance from the sun Then the ratio of the magnitudes of maximum and minimum gravitational forces between them is A.r1:r2 B.r2:r1 C.r1^2:r2^2 D.r2^2:r1^2

A car of 1000 kg, is accelerating due to a net force 1200 N. If 4 people of mass 50 Kg board the car, then what is the new acceleration? (in ms2) ___

Name the gate represented by the following circuit.

Two identical spheres are placed in contact with each other. The force of gravitation between the spheres will be proportional to (R = radius of each sphere)

A block of mass 'm' is initially lying on a wedge of mass 'M' with an angle of inclination θ, as shown in the figure. Calculate the displacement of the wedge when the block reaches bottom of the wedge.

A metallic sphere of radius r and specific heat S is rotated about an axis passing through its centre of mass at an angular speed of n rotations per second. It is suddenly stopped and 50% of its energy is used in increasing its temperature. Then, the rise in temperature of the sphere is

A body initially at 80∘C cools to 64∘C in 5 minutes and to 52∘C after another 5 minutes. The temperature of the surroundings is

A mass of M kg is suspended by a weightless string. The horizontal force required to displace it until the string makes an angel of 45∘ with the initial vertical direction is

A man has a weight 105 N on a weighing machine kept near the north pole of the earth. What will be the reduction in the weight of the man if he moves to the equator? Take g=9.8 m/s2, radius of earth (R)=6400 km, angular speed of the earth ω=7.27×10−5 rad/s.

The angular velocity of a body changes from ω1 to ω2 without applying a torque but changing moment of inertia. The ratio of corresponding radii of gyration

When a charged particle enters a magnetic field in a direction perpendicular to the field, which one of the following does not change?

A fixed horizontal wire A carrying current of 8 A supports another horizontal wire B carrying current 10 A , hanging in air at a distance 5 cm below the wire A. Considering the direction of current in two wires as same. Find the weight of wire B.

If a train travelling at 30 m/s is to be brought to rest in a distance of 200 m, then its retardation should be

relationship is called

The figure illustrates plane figures made of thin conductors which are located in a uniform magnetic field directed away from the reader, perpendicular to the plane of drawing. The magnetic field starts decreasing. The currents induced in these loops are directed as

If a rubber ball is taken at the depth of 200 m in a pool its volume decreases by 0.2%. If the density of the water is 103 kg/m3 and g=10 m/s2, then the volume elasticity in N/m2 will be:

Above graph shows stopping potential versus 1wavelength for three metals, then

The blocks (m2&gt;m1) are held in such a manner that spring is unstretched initially. Consider the situation at the time of release of the block (t=0) and short time after releasing the block (t&gt;0). Accelerations of the blocks of masses m1 and m2 are a1 and a2 respectively

An 8m long copper wire and a 4m long steel wire, each of cross-section 0.5 cm2 are fastened end to end and stretched by a 500 N force. The elastic potential energy of the system is (YCopper=1×1011Nm−2;Ysteel=2×1011Nm−2)

A mirror in the first quadrant is in the shape of a hyperbola whose equation is xy=1. A light source in the second quadrant emits a beam of light that hits the mirror at the point (2,12). If the reflected ray is parallel to the y−axis, the slope of the incident beam is

Two pendula start swinging simultaneously. By the time first pendulum makes 20 oscillations, 2nd pendulum makes 15 oscillations. The ratio of their lengths is

The vertical component of earth's magnetic field is zero at or The earth's magnetic field always has a vertical component except at the

A cord is used to lower vertically a block of mass M by a distance d with constant downward acceleration g4 . Work done by the cord on the block is

A tuning fork (pair) produces 4 beats/sec with another fork of frequency 288 Hz. A little wax is placed on the unknown fork and it then produces 2 beats/sec. The frequency of the unknown fork is

Two blocks of mass m and 2m are connected as shown in figure. A force F is acting on the block of mass 4m. Pulley is massless and string is light and inextensible. All the surfaces are smooth. Contact force between ground and the 4m mass under the previous problem condition is

Following figure shows different combinations of identical bulbs connected to identical battery(ies). Which option is correct regarding the total power dissipated in the circuit?

In Young's double slit experiment, the distance of the nth dark fringe from the centre is-

What are the applications of elasticity?

Particles of masses 1 g, 2 g, 3 g, ......, 100 g are kept at the marks 1 cm, 2 cm, 3 cm, ......., 100 cm respectively on metre scale. Find the moment of inertia of the system of particles about a perpendicular bisector of the metre scale.

Seven homogeneous bricks,each of length L, are arranged as shown in figure (9-E2).Each brick is displaced with respect to the one in contact by L/10.Find the x-coordinate of the centre of mass relative to the origin shown.

A pilot takes off from an airport at 15∘S latitude and flies 55∘ due North. What latitude has the pilot reached?

The point from where a ball of mass 2 kg is projected is taken as the origin of the co-ordinate axes. The x and y components of its displacement are given by x=6t and y=8t−5t2. Find the impulse ( in kg m/s) acting on it between the time t=0 to t=2 seconds

In the circuit shown, X is joined to Y for a long time, and then X is joined to Z. The total heat produced in R2 is

A T shaped object with dimensions shown in the figure is lying on a smooth floor. A force →F is applied at the point P parallel to AB such that the object has only the translational motion without rotation. Find the location of P with respect to C.

Water is filled in a uniform container of area of cross section A. A hole of cross section area a (

Three smooth pulleys are connected by a light string. A mass m is attached to the pulley P3. Assume the strings between two pulleys and between the pulley and the support to be vertical. If all the pulleys are massless then the tension in the string over the pulleys is

The blocks (m2>m1) are held in such a manner that spring is unstretched initially. Consider the situation at the time of release of the block (t=0) and short time after releasing the block (t>0). Accelerations of the blocks of masses m1 and m2 are a1 and a2 respectively