50278 + Interview Questions in Physics

1.	Choose the correct statement
Answer» Choose the correct statement

1.

Choose the correct statement

Answer»

Choose the correct statement

2.	The function y = 4cos2x is periodic with period
Answer» The function y = 4cos2x is periodic with period

Discussion

3.	The output of a 2-input OR gate is zero only when its:
Answer» The output of a 2-input OR gate is zero only when its:

Discussion

4.	Ampere’s circuital law is analogous to a law in electrostatics.That law is
Answer» Ampere’s circuital law is analogous to a law in electrostatics.That law is

Discussion

5.	A block of mass 2 kg slides down an incline plane of inclination 30∘. The coefficient of friction between block and plane is 0.5. The contact force between block and incline plane is :
Answer» A block of mass $2 kg$ slides down an incline plane of inclination $30^{\circ}$ . The coefficient of friction between block and plane is $0.5$ . The contact force between block and incline plane is :

Discussion

6.	Density of a unit cell is same as the
Answer» Density of a unit cell is same as the

Discussion

7.	A gaseous mixture containing He, CH4 and SO2 was allowed to effuse through a fine hole. Find what molar ratio of gases comes out initially, if the mixture contains He, CH4 and SO2 in 1:2:3 mole ratio.
Answer» A gaseous mixture containing $H e, C H_{4}$ and $S O_{2}$ was allowed to effuse through a fine hole. Find what molar ratio of gases comes out initially, if the mixture contains $H e, C H_{4}$ and $S O_{2}$ in $1 : 2 : 3$ mole ratio.

Discussion

8.	Column - I gives a list of possible set of parameter measures in some experiments. The variations of the parameters in the form of graphs are shown in Column - II. Match the set of parameters given in Column - I with the graphs given in Column - II.
Answer» Column - I gives a list of possible set of parameter measures in some experiments. The variations of the parameters in the form of graphs are shown in Column - II. Match the set of parameters given in Column - I with the graphs given in Column - II.

Discussion

9.	What is the effect of increase of pressure on speed of sound in air.
Answer» What is the effect of increase of pressure on speed of sound in air.

Discussion

10.	What will happen if you chop or break an atom?what will happen to the electron(s)?will they be moving still?what about the protons and neutrons?will there be any energy emitted?
Answer» What will happen if you chop or break an atom?what will happen to the electron(s)?will they be moving still?what about the protons and neutrons?will there be any energy emitted?

Discussion

11.	The correct output for the given circuit is
Answer» The correct output for the given circuit is

Discussion

12.	In the following circuit p-n-junction diodes D1,D2 and D3 are ideal for the following potential of A and B, the correct increasing order of resistance between A and B will be - (i)−10 V,−5 V(ii)−5 V,−10 V(iii)−4 V,−12 V
Answer» In the following circuit p-n-junction diodes $D_{1}, D_{2}$ and $D_{3}$ are ideal for the following potential of $A$ and $B$ , the correct increasing order of resistance between $A$ and $B$ will be - $(i) - 10 V, - 5 V (i i) - 5 V, - 10 V (i i i) - 4 V, - 12 V$

Discussion

13.	A body of mass 2 kg starts moving uniformly from the point (1,2,3) to point (2,3,5) in 3 seconds. The net work done during 3 seconds is
Answer» A body of mass $2 kg$ starts moving uniformly from the point $(1, 2, 3)$ to point $(2, 3, 5)$ in 3 seconds. The net work done during 3 seconds is

Discussion

14.	Let →a=2^i−3^j+4^k,→b=^i−^j+2^k and →c=6^i−3^j+^k, then find →d which is perpendicular to both →a and →b and →c.→d=2
Answer» Let $\to a = 2^i - 3^j + 4^k, \to b =^i -^j + 2^k$ and $\to c = 6^i - 3^j +^k$ , then find $\to d$ which is perpendicular to both $\to a$ and $\to b$ and $\to c . \to d = 2$

Discussion

15.	A mass of 2 kg is whirled in a horizontal circle by means of a string at an initial speed of 5 revolutions per minute. Keeping the radius constant the tension in the string is doubled. The new speed is nearly
Answer» A mass of 2 kg is whirled in a horizontal circle by means of a string at an initial speed of 5 revolutions per minute. Keeping the radius constant the tension in the string is doubled. The new speed is nearly

Discussion

16.	A body of mass 2 kg is being dragged with uniform velocity of 2 m/s on a rough horizontal plane. The coefficient of friction between the body and the surface is 0.20. The amount of heat generated in 5 sec is (J =4.2 joule/cal and g=9.8 m/s2)
Answer» A body of mass 2 kg is being dragged with uniform velocity of 2 m/s on a rough horizontal plane. The coefficient of friction between the body and the surface is 0.20. The amount of heat generated in 5 sec is (J =4.2 joule/cal and g=9.8 $m / s^{2}$ )

Discussion

17.	A particle is constrained to move on a straight line path. It returns to the starting point after 10 sec. The total distance covered by the particle during this time is 30 m. Which of the following statements about the motion of the particle is false
Answer» A particle is constrained to move on a straight line path. It returns to the starting point after 10 sec. The total distance covered by the particle during this time is 30 m. Which of the following statements about the motion of the particle is false

Discussion

18.	An artificial satellite moving in a circular orbit around the earth has a total (kinetic + potential) energy E0. Its potential energy is
Answer» An artificial satellite moving in a circular orbit around the earth has a total (kinetic + potential) energy $E_{0}$ . Its potential energy is

Discussion

19.	Considering the case of a parallel plate capacitor being charged, show how one is required to generalize Ampere's circuital law to include the term due to displacement current.
Answer» Considering the case of a parallel plate capacitor being charged, show how one is required to generalize Ampere's circuital law to include the term due to displacement current.

Discussion

20.	A glass capillary tube of inner diameter 0.28 mm is lowered vertically into water in a vessel. The pressure to be applied on the water in the capillary tube so that water level in the tube is same as that in the vessel (in N/m2) is (Surface tension of water =0.07 N/m and atmospheric pressure =105 N/m2)
Answer» A glass capillary tube of inner diameter $0.28 mm$ is lowered vertically into water in a vessel. The pressure to be applied on the water in the capillary tube so that water level in the tube is same as that in the vessel $({in N/m}^{2})$ is (Surface tension of water $= 0.07 N/m$ and atmospheric pressure $= 10^{5} {N/m}^{2})$

Discussion

21.	Two identical point charges are placed at a separation of d. P is a point on the line joining the charges, at a distance x from any one charge. The field at P is E. E is plotted against x for values of x from close to zero to slightly less than d. Which of the following represents the resulting curve?
Answer» Two identical point charges are placed at a separation of d. P is a point on the line joining the charges, at a distance x from any one charge. The field at P is E. E is plotted against x for values of x from close to zero to slightly less than d. Which of the following represents the resulting curve?

Discussion

22.	If the vectors →a=2^i−3^j+4^k and →b=−4^i+x^j−8^k are collinear, the x =
Answer» If the vectors $\to a = 2^i - 3^j + 4^k a n d \to b = - 4^i + x^j - 8^k$ are collinear, the x =

Discussion

23.	A vibration magnetometer consists of two identical bar magnets placed one over the other such that they are perpendicular and bisect each other. The time period of oscillation in a horizontal magnetic field is 254 seconds. One of the magnets is removed and if the other magnet oscillates in the same field, then the time period in seconds is
Answer» A vibration magnetometer consists of two identical bar magnets placed one over the other such that they are perpendicular and bisect each other. The time period of oscillation in a horizontal magnetic field is $2^{\frac{5}{4}}$ seconds. One of the magnets is removed and if the other magnet oscillates in the same field, then the time period in seconds is

Discussion

24.	A boy is seated in a revolving chair revolving at an angular speed of 120 revolutions per minute. Two heavy balls form part of the revolving system and the boy can pull the balls closer to himself or may push them apart. If by pulling the balls closer, the boy decreases the moment of inertia of the system from 6 kg-m2 to 2 kg-m2, what will be the new angular speed ?
Answer» A boy is seated in a revolving chair revolving at an angular speed of 120 revolutions per minute. Two heavy balls form part of the revolving system and the boy can pull the balls closer to himself or may push them apart. If by pulling the balls closer, the boy decreases the moment of inertia of the system from 6 ${kg-m}^{2}$ to 2 ${kg-m}^{2}$ , what will be the new angular speed ?

Discussion

25.	Why is the frequency of a.c always greater than 1??
Answer» Why is the frequency of a.c always greater than 1??

Discussion

26.	The conductivity of a material is 5 mho/m. What is it’s resistivity?
Answer» The conductivity of a material is 5 mho/m. What is it’s resistivity?

Discussion

27.	A trolley of mass m is connected to two identical springs, each of force constant k, as shown in figure. The trolley is displaced from its equilibrium position by a distance x and released. The trolley executes simple harmonic motion of period T. After some time it comes to rest due to friction. The total energy dissipated as heat is (assume the damping force to be weak)
Answer» A trolley of mass m is connected to two identical springs, each of force constant k, as shown in figure. The trolley is displaced from its equilibrium position by a distance x and released. The trolley executes simple harmonic motion of period T. After some time it comes to rest due to friction. The total energy dissipated as heat is (assume the damping force to be weak)

27.

A trolley of mass m is connected to two identical springs, each of force constant k, as shown in figure. The trolley is displaced from its equilibrium position by a distance x and released. The trolley executes simple harmonic motion of period T. After some time it comes to rest due to friction. The total energy dissipated as heat is (assume the damping force to be weak)

Answer»

A trolley of mass m is connected to two identical springs, each of force constant k, as shown in figure. The trolley is displaced from its equilibrium position by a distance x and released. The trolley executes simple harmonic motion of period T. After some time it comes to rest due to friction. The total energy dissipated as heat is (assume the damping force to be weak)

Discussion

28.	A rod of length 4 m is placed along x-axis. The rod is non-uniform and the mass per unit length of rod varies as λ=x2−4x+4 then center of mass of rod is at
Answer» A rod of length $4 m$ is placed along x-axis. The rod is non-uniform and the mass per unit length of rod varies as $λ = x^{2} - 4 x + 4$ then center of mass of rod is at

Discussion

29.	A metallic sphere of radius 2 m is charged in air to a potential of 3000 V. Calculate the energy stored in the sphere.
Answer» A metallic sphere of radius 2 m is charged in air to a potential of 3000 V. Calculate the energy stored in the sphere.

Discussion

30.	A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by
Answer» A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by

30.

A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by

Answer»

A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by

Discussion

31.	A hemispherical vessel of radius R moving with a constant velocity v0 and containing a ball is suddenly halted. Find the height by which ball rise in the vessel, provided the surface is smooth is
Answer» A hemispherical vessel of radius R moving with a constant velocity $v_{0}$ and containing a ball is suddenly halted. Find the height by which ball rise in the vessel, provided the surface is smooth is

Discussion

32.	Two identical P-N junctions may be connected in series with a battery in three ways. The potential drops across the two P-N junctions are equal in
Answer» Two identical P-N junctions may be connected in series with a battery in three ways. The potential drops across the two P-N junctions are equal in

32.

Two identical P-N junctions may be connected in series with a battery in three ways. The potential drops across the two P-N junctions are equal in

Answer»

Two identical P-N junctions may be connected in series with a battery in three ways. The potential drops across the two P-N junctions are equal in

Discussion

33.	Assertion: A proton and an α - particle are projected with the same kinetic energy at right angle to a uniform magnetic field, then the α - particle will move along a circular path of smaller radius than the proton. Reason : Bqv=mv2r holds good for the charged particle moving in a circular path in a uniform magnetic field. Choose the most appropriate correct option:
Answer» Assertion: A proton and an $α$ - particle are projected with the same kinetic energy at right angle to a uniform magnetic field, then the $α$ - particle will move along a circular path of smaller radius than the proton. Reason : $B q v = \frac{m v^{2}}{r}$ holds good for the charged particle moving in a circular path in a uniform magnetic field. Choose the most appropriate correct option:

33.

Assertion: A proton and an α - particle are projected with the same kinetic energy at right angle to a uniform magnetic field, then the α - particle will move along a circular path of smaller radius than the proton. Reason : Bqv=mv2r holds good for the charged particle moving in a circular path in a uniform magnetic field. Choose the most appropriate correct option:

Answer»

Assertion: A proton and an $α$ - particle are projected with the same kinetic energy at right angle to a uniform magnetic field, then the $α$ - particle will move along a circular path of smaller radius than the proton.

Reason : $B q v = \frac{m v^{2}}{r}$ holds good for the charged particle moving in a circular path in a uniform magnetic field.

Choose the most appropriate correct option:

Discussion

34.	A boy of mass m stands at the edge of a circular platform of radius R capable of rotating freely about its axis. The moment of inertia of the platform is I. The system is rest. A friend of the boy throws a ball of mass m with a velocity v horizontally. The boy on the platform catches it when it passes tangential to the platform. Find the angular velocity of the system after the boy catches the ball.
Answer» A boy of mass $m$ stands at the edge of a circular platform of radius $R$ capable of rotating freely about its axis. The moment of inertia of the platform is $I$ . The system is rest. A friend of the boy throws a ball of mass $m$ with a velocity $v$ horizontally. The boy on the platform catches it when it passes tangential to the platform. Find the angular velocity of the system after the boy catches the ball.

Discussion

35.	A stone of mass 5 kg falls from the top of a 50 m high building and penetrates 1 m deep in the sand. Find the time taken to penetrate.
Answer» A stone of mass 5 kg falls from the top of a 50 m high building and penetrates 1 m deep in the sand. Find the time taken to penetrate.

Discussion

36.	A uniform solid sphere of mass m and radius R is placed on a horizontal surface. A horizontal linear impulse P is applied at a height R2 above its center. Find the velocity of center of mass and angular velocity of sphere just after the impulse is applied.
Answer» A uniform solid sphere of mass m and radius R is placed on a horizontal surface. A horizontal linear impulse P is applied at a height $\frac{R}{2}$ above its center. Find the velocity of center of mass and angular velocity of sphere just after the impulse is applied.

36.

A uniform solid sphere of mass m and radius R is placed on a horizontal surface. A horizontal linear impulse P is applied at a height R2 above its center. Find the velocity of center of mass and angular velocity of sphere just after the impulse is applied.

Answer»

A uniform solid sphere of mass m and radius R is placed on a horizontal surface. A horizontal linear impulse P is applied at a height $\frac{R}{2}$ above its center. Find the velocity of center of mass and angular velocity of sphere just after the impulse is applied.

Discussion

37.	A moving particle of mass 'm' makes a head-on collision with a particle of mass '2m' initially at rest. If the collision is perfectly elastic, the percentage loss of energy of the colliding particle is
Answer» A moving particle of mass 'm' makes a head-on collision with a particle of mass '2m' initially at rest. If the collision is perfectly elastic, the percentage loss of energy of the colliding particle is

Discussion

38.	We know that Ohm Law is V = IR PROBLEM - Suppose I take a conducting Rod and let us say that it's one end is A and other is B. Suppose I give a potential difference at A of quantity V and initally my rod resistance is R when the length of rod is L. What will happen to V and I if I increase the resistance of rod by increasing or decreasing length? To balance the equation V = I R who will change the value V or I. MY APPROACH--- What I think is that V can't change since it is a constantly given by source (assumed) so I think value of I will decrease. This question is borned out of my mind so I also do not know ''Is questions I have uploaded is meaningless?' Help me in finding correct answer. In my problem there is no image because I don't think it is necessary and I have assumed a constant temperature.
Answer» We know that Ohm Law is V = IR PROBLEM - Suppose I take a conducting Rod and let us say that it's one end is A and other is B. Suppose I give a potential difference at A of quantity V and initally my rod resistance is R when the length of rod is L. What will happen to V and I if I increase the resistance of rod by increasing or decreasing length? To balance the equation V = I R who will change the value V or I. MY APPROACH--- What I think is that V can't change since it is a constantly given by source (assumed) so I think value of I will decrease. This question is borned out of my mind so I also do not know ''Is questions I have uploaded is meaningless?' Help me in finding correct answer. In my problem there is no image because I don't think it is necessary and I have assumed a constant temperature.

38.

We know that Ohm Law is V = IR PROBLEM - Suppose I take a conducting Rod and let us say that it's one end is A and other is B. Suppose I give a potential difference at A of quantity V and initally my rod resistance is R when the length of rod is L. What will happen to V and I if I increase the resistance of rod by increasing or decreasing length? To balance the equation V = I R who will change the value V or I. MY APPROACH--- What I think is that V can't change since it is a constantly given by source (assumed) so I think value of I will decrease. This question is borned out of my mind so I also do not know ''Is questions I have uploaded is meaningless?' Help me in finding correct answer. In my problem there is no image because I don't think it is necessary and I have assumed a constant temperature.

Answer»

We know that Ohm Law is V = IR

PROBLEM -

Suppose I take a conducting Rod and let us say that it's one end is A and other is B. Suppose I give a potential difference at A of quantity V and initally my rod resistance is R when the length of rod is L.

What will happen to V and I if I increase the resistance of rod by increasing or decreasing length?

To balance the equation V = I R who will change the value V or I.

MY APPROACH---

What I think is that V can't change since it is a constantly given by source (assumed) so I think value of I will decrease.

This question is borned out of my mind so I also do not know ''Is questions I have uploaded is meaningless?'

Help me in finding correct answer.

In my problem there is no image because I don't think it is necessary and I have assumed a constant temperature.

Discussion

39.	If we take units of mass, length and time as 2 kg, 2 m and 2 s respectively then the unit of energy will be
Answer» If we take units of mass, length and time as $2 kg, 2 m$ and $2 s$ respectively then the unit of energy will be

Discussion

40.	A 5 kg block has a rope of mass 2 kg attached to its underside and a 3 kg block is suspended from the other end of the rope. The whole system is accelerated upward at 2 ms−2 by an external force F0. What is the tension at middle point of the rope and F0? (g=10 ms−2)
Answer» A $5 kg$ block has a rope of mass $2 kg$ attached to its underside and a $3 kg$ block is suspended from the other end of the rope. The whole system is accelerated upward at $2 {ms}^{- 2}$ by an external force $F_{0}$ . What is the tension at middle point of the rope and $F_{0}$ ? $(g = 10 {ms}^{- 2})$

Discussion

41.	A solid sphere of radius R and density ρ is attached to one end of a massless spring of force constant k. The other end of the spring is connected to another solid sphere of radius R and density 3ρ. The complete arrangement is placed in a liquid of density 2ρ and is allowed to reach equilibrium. The correct statement(s) is (are)
Answer» A solid sphere of radius R and density $ρ$ is attached to one end of a massless spring of force constant k. The other end of the spring is connected to another solid sphere of radius R and density $3 ρ$ . The complete arrangement is placed in a liquid of density $2 ρ$ and is allowed to reach equilibrium. The correct statement(s) is (are)

Discussion

42.	A block of mass m is kept on a horizontal ruler. The friction coefficient between the ruler and the block is μ. The ruler is fixed at one end and the block is at a distance L from the fixed end. The ruler is rotated about the fixed end in the horizontal plane through the fixed end. If the angular speed of the ruler is uniformly increased from zero at an angular acceleration α, at what angular speed will the block slip?
Answer» A block of mass m is kept on a horizontal ruler. The friction coefficient between the ruler and the block is μ. The ruler is fixed at one end and the block is at a distance L from the fixed end. The ruler is rotated about the fixed end in the horizontal plane through the fixed end. If the angular speed of the ruler is uniformly increased from zero at an angular acceleration α, at what angular speed will the block slip?

Discussion

43.	In the given figure a block of mass M and density ρ is immersed in liquid of density σ. The block is attached to the spring from top and string from bottom. Elongation in the spring when string is tight is x and spring constant is Mg3x. Column 1 Column 2 Column 3 (Tension developed in string) (Force generated in spring)(I)If ρ=2g/cc(i)T=4Mg3(P)F=Mg3 σ=1g/cc (II)If ρ=1g/cc(ii)T=Mg3(Q)F=0 σ=1g/cc (III)If ρ=1g/cc(iii)T=Mg2(R)F=Mg2 σ=2g/cc (IV)If ρ=1.2g/cc(iv)T=0(R)F=4Mg3 σ=0.8g/cc Which of the following is true for ρ>σ?
Answer» In the given figure a block of mass M and density $ρ$ is immersed in liquid of density $σ$ . The block is attached to the spring from top and string from bottom. Elongation in the spring when string is tight is x and spring constant is $\frac{M g}{3 x}$ . $\begin{matrix} C o l u m n 1 & C o l u m n 2 & C o l u m n 3 (T e n s i o n d e v e l o p e d i n s t r i n g) & (F o r c e g e n e r a t e d i n s p r i n g) (I) & I f ρ = 2 g / c c & (i) & T = \frac{4 M g}{3} & (P) & F = \frac{M g}{3} σ = 1 g / c c (I I) & I f ρ = 1 g / c c & (i i) & T = \frac{M g}{3} & (Q) & F = 0 σ = 1 g / c c (I I I) & I f ρ = 1 g / c c & (i i i) & T = \frac{M g}{2} & (R) & F = \frac{M g}{2} σ = 2 g / c c (I V) & I f ρ = 1.2 g / c c & (i v) & T = 0 & (R) & F = \frac{4 M g}{3} σ = 0.8 g / c c \end{matrix}$ Which of the following is true for $ρ > σ$ ?

Discussion

44.	Two bullets are fired simultaneously, horizontally and with different speeds from the same place. Which bullet will hit the ground first
Answer» Two bullets are fired simultaneously, horizontally and with different speeds from the same place. Which bullet will hit the ground first

Discussion

45.	A solenoid has a length 1 m and inner diameter 4 cm and it carries a current of 5 A. It consists of five close packed layers, each with 800 turns along its length. The magnitude of the magnetic field at the centre is nearly equal to
Answer» A solenoid has a length 1 m and inner diameter 4 cm and it carries a current of 5 A. It consists of five close packed layers, each with 800 turns along its length. The magnitude of the magnetic field at the centre is nearly equal to

Discussion

46.	Two spherical bodies A (radius 6 cm) and B (radius 18 cm) are at temperatures T1 and T2 , respectively. The maximum intensity in the emission spectrum of A is at 500 nm and in that of B is at 1500 nm. Considering them to be black bodies, what will be the ratio of the rate of total energy radiated by A to that of B ?
Answer» Two spherical bodies A (radius $6 cm)$ and B (radius $18 cm)$ are at temperatures $T_{1}$ and $T_{2}$ , respectively. The maximum intensity in the emission spectrum of A is at $500 nm$ and in that of B is at $1500 nm$ . Considering them to be black bodies, what will be the ratio of the rate of total energy radiated by A to that of B ?

Discussion

47.	A uniform rope of length L and mass m1 hangs vertically from a rigid support. A block of mass m2 is attached to the free end of the rope. A transverse pulse of wavelength λ1 is produced at the lower end of the rope. The wavelength of the pulse when it reaches the top of the rope is λ2. The ratio λ2λ1 is
Answer» A uniform rope of length $L$ and mass $m_{1}$ hangs vertically from a rigid support. A block of mass $m_{2}$ is attached to the free end of the rope. A transverse pulse of wavelength $λ_{1}$ is produced at the lower end of the rope. The wavelength of the pulse when it reaches the top of the rope is $λ_{2}$ . The ratio $\frac{λ_{2}}{λ_{1}}$ is

Discussion

48.	Find the equivalent resistance between A and E (resistance of each resistor is R).
Answer» Find the equivalent resistance between A and E (resistance of each resistor is $R$ ).

Discussion

49.	The density of a substance at 200C and 1200C are 1.1 g/cc and 1 g/cc respectively. The coefficient of cubical expansion of the solid is.
Answer» The density of a substance at $20^{0} C a n d 120^{0} C$ are $1.1 g / c c a n d 1 g / c c$ respectively. The coefficient of cubical expansion of the solid is.

Discussion

50.	As Newton's third law says, we can stand on ground because we apply a force on ground because of our weight, and the ground resists. We cannot stand on water because water cannot resist the force applied by our weight. But we can swim on water because we push the water backwards, and water resists and pushes us forward. How can water resist us while swimming but not while standing on the water surface?
Answer» As Newton's third law says, we can stand on ground because we apply a force on ground because of our weight, and the ground resists. We cannot stand on water because water cannot resist the force applied by our weight. But we can swim on water because we push the water backwards, and water resists and pushes us forward. How can water resist us while swimming but not while standing on the water surface?

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Choose the correct statement

The function y = 4cos2x is periodic with period

The output of a 2-input OR gate is zero only when its:

Ampere’s circuital law is analogous to a law in electrostatics.That law is

A block of mass 2 kg slides down an incline plane of inclination 30∘. The coefficient of friction between block and plane is 0.5. The contact force between block and incline plane is :

Density of a unit cell is same as the

A gaseous mixture containing He, CH4 and SO2 was allowed to effuse through a fine hole. Find what molar ratio of gases comes out initially, if the mixture contains He, CH4 and SO2 in 1:2:3 mole ratio.

Column - I gives a list of possible set of parameter measures in some experiments. The variations of the parameters in the form of graphs are shown in Column - II. Match the set of parameters given in Column - I with the graphs given in Column - II.

What is the effect of increase of pressure on speed of sound in air.

What will happen if you chop or break an atom?what will happen to the electron(s)?will they be moving still?what about the protons and neutrons?will there be any energy emitted?

The correct output for the given circuit is

In the following circuit p-n-junction diodes D1,D2 and D3 are ideal for the following potential of A and B, the correct increasing order of resistance between A and B will be - (i)−10 V,−5 V(ii)−5 V,−10 V(iii)−4 V,−12 V

A body of mass 2 kg starts moving uniformly from the point (1,2,3) to point (2,3,5) in 3 seconds. The net work done during 3 seconds is

Let →a=2^i−3^j+4^k,→b=^i−^j+2^k and →c=6^i−3^j+^k, then find →d which is perpendicular to both →a and →b and →c.→d=2

A mass of 2 kg is whirled in a horizontal circle by means of a string at an initial speed of 5 revolutions per minute. Keeping the radius constant the tension in the string is doubled. The new speed is nearly

A body of mass 2 kg is being dragged with uniform velocity of 2 m/s on a rough horizontal plane. The coefficient of friction between the body and the surface is 0.20. The amount of heat generated in 5 sec is (J =4.2 joule/cal and g=9.8 m/s2)

A particle is constrained to move on a straight line path. It returns to the starting point after 10 sec. The total distance covered by the particle during this time is 30 m. Which of the following statements about the motion of the particle is false

An artificial satellite moving in a circular orbit around the earth has a total (kinetic + potential) energy E0. Its potential energy is

Considering the case of a parallel plate capacitor being charged, show how one is required to generalize Ampere's circuital law to include the term due to displacement current.

If the vectors →a=2^i−3^j+4^k and →b=−4^i+x^j−8^k are collinear, the x =

Why is the frequency of a.c always greater than 1??

The conductivity of a material is 5 mho/m. What is it’s resistivity?

A rod of length 4 m is placed along x-axis. The rod is non-uniform and the mass per unit length of rod varies as λ=x2−4x+4 then center of mass of rod is at

A metallic sphere of radius 2 m is charged in air to a potential of 3000 V. Calculate the energy stored in the sphere.

A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by

A hemispherical vessel of radius R moving with a constant velocity v0 and containing a ball is suddenly halted. Find the height by which ball rise in the vessel, provided the surface is smooth is

Two identical P-N junctions may be connected in series with a battery in three ways. The potential drops across the two P-N junctions are equal in

A stone of mass 5 kg falls from the top of a 50 m high building and penetrates 1 m deep in the sand. Find the time taken to penetrate.

A uniform solid sphere of mass m and radius R is placed on a horizontal surface. A horizontal linear impulse P is applied at a height R2 above its center. Find the velocity of center of mass and angular velocity of sphere just after the impulse is applied.

A moving particle of mass 'm' makes a head-on collision with a particle of mass '2m' initially at rest. If the collision is perfectly elastic, the percentage loss of energy of the colliding particle is

If we take units of mass, length and time as 2 kg, 2 m and 2 s respectively then the unit of energy will be

A 5 kg block has a rope of mass 2 kg attached to its underside and a 3 kg block is suspended from the other end of the rope. The whole system is accelerated upward at 2 ms−2 by an external force F0. What is the tension at middle point of the rope and F0? (g=10 ms−2)

Two bullets are fired simultaneously, horizontally and with different speeds from the same place. Which bullet will hit the ground first

A solenoid has a length 1 m and inner diameter 4 cm and it carries a current of 5 A. It consists of five close packed layers, each with 800 turns along its length. The magnitude of the magnetic field at the centre is nearly equal to

Find the equivalent resistance between A and E (resistance of each resistor is R).

The density of a substance at 200C and 1200C are 1.1 g/cc and 1 g/cc respectively. The coefficient of cubical expansion of the solid is.