50278 + Interview Questions in Physics

1.	A diver at a depth of 12m in water sees the sky in a cone of semi vertical anglea) sin^-1(4/3) b) tan^-1(4/3) c) sin^-1(3/4) d) 90degrees
Answer» A diver at a depth of 12m in water sees the sky in a cone of semi vertical angle a) sin^-1(4/3) b) tan^-1(4/3) c) sin^-1(3/4) d) 90degrees

Discussion

2.	Why can we say that speed is equal to time upon length
Answer» Why can we say that speed is equal to time upon length

Discussion

3.	Shown in the figure, is a conductor carrying current I. The net magnetic induction at the point O is given by xμ0Iθ24πR. Find the value of x.[Point O is the common center of all the three arcs.]
Answer» Shown in the figure, is a conductor carrying current $I$ . The net magnetic induction at the point $O$ is given by $\frac{x μ_{0} I θ}{24 π R}$ . Find the value of $x$ . [Point $O$ is the common center of all the three arcs.]

Discussion

4.	In the diagram shown, the blocks A, B and C weight 3 kg, 4 kg and 5 kg respectively. The coefficient of sliding friction between any two surfaces is 0.25. A is held at rest by a massless rigid rod fixed to the wall while B and C are connected by a light flexible cord passing round a frictionless pulley. The force F necessary to drag C along the horizontal surface to the left at constant speed is (Assume that the arrangement shown in the diagram, B on C and A on B is maintained all through and g=10 m/s2)
Answer» In the diagram shown, the blocks $A, B$ and $C$ weight $3 kg$ , $4 kg$ and $5 kg$ respectively. The coefficient of sliding friction between any two surfaces is $0.25$ . $A$ is held at rest by a massless rigid rod fixed to the wall while $B$ and $C$ are connected by a light flexible cord passing round a frictionless pulley. The force $F$ necessary to drag $C$ along the horizontal surface to the left at constant speed is (Assume that the arrangement shown in the diagram, $B$ on $C$ and $A$ on $B$ is maintained all through and $g = 10 {m/s}^{2}$ )

Discussion

5.	The value of sec(sec−15) is
Answer» The value of $sec ({sec}^{- 1} 5)$ is

Discussion

6.	A circuit contains an ammeter, a battery of 30 V and a resistance of 40.8 ohm all connected in series. If the ammeter has a coil of resistance 480 ohm and a shunt of resistance 20 ohm, the reading in the ammeter will be
Answer» A circuit contains an ammeter, a battery of $30 V$ and a resistance of $40.8$ ohm all connected in series. If the ammeter has a coil of resistance $480$ ohm and a shunt of resistance $20$ ohm, the reading in the ammeter will be

Discussion

7.	a spring is loaded with two blocks of masses m1 and m2,where m1 is rigidly fixed with the spring and m2 is just kept on the block m1.the maximum energy of oscillation is possible for the system having the block m2 in contact with m1 is (1)m1^2g^2/2k (2)m2^2g^2/2k (3)(m1+m2)^2g^2/2k (4)none of these
Answer» a spring is loaded with two blocks of masses m1 and m2,where m1 is rigidly fixed with the spring and m2 is just kept on the block m1.the maximum energy of oscillation is possible for the system having the block m2 in contact with m1 is (1)m1^2g^2/2k (2)m2^2g^2/2k (3)(m1+m2)^2g^2/2k (4)none of these

Discussion

8.	77.An ammeter and a volt meter of resistance R are connected in series to an electric cell of negligible internal resistance.Their readings are A and V respectively.If another resistance R is connected in parallel with the voltmeter then
Answer» 77.An ammeter and a volt meter of resistance R are connected in series to an electric cell of negligible internal resistance.Their readings are A and V respectively.If another resistance R is connected in parallel with the voltmeter then

Discussion

9.	Why opposite signs are repelling each other in molecular bonding ?
Answer» Why opposite signs are repelling each other in molecular bonding ?

Discussion

10.	A small body of mass 0.10 kg is executing S.H.M. of amplitude 1.0 m and period 0.20 sec. The maximum force acting on it is
Answer» A small body of mass 0.10 kg is executing S.H.M. of amplitude 1.0 m and period 0.20 sec. The maximum force acting on it is

Discussion

11.	An equiconvex lens has power P and radii of curvature R. The radius of curvature of the surface of a plano-convex lens made of the same material with power 1.5P is
Answer» An equiconvex lens has power $P$ and radii of curvature $R$ . The radius of curvature of the surface of a plano-convex lens made of the same material with power $1.5 P$ is

Discussion

12.	Two particles A & B are projected with same speed at angles of projections (90 -a) & (90 -2a) .If their horizontal ranges are equal ,then value of 'a' is a) 15b) 30c)7.5d)22.5
Answer» Two particles A & B are projected with same speed at angles of projections (90 -a) & (90 -2a) .If their horizontal ranges are equal ,then value of 'a' is a) 15 b) 30 c)7.5 d)22.5

Discussion

13.	In the given potentiometer circuit length of the wire AB is 3 m and resistance is R=4.5 Ω. The length AC for no deflection in galvanometer is
Answer» In the given potentiometer circuit length of the wire $AB$ is $3 m$ and resistance is $R = 4.5 Ω$ . The length $AC$ for no deflection in galvanometer is

Discussion

14.	Consider a Boolean expression.f=(B+BC)(B+¯¯¯¯BC)(B+D)The minimum number of NAND-gates required to implement this function ′f′ will be __________0
Answer» Consider a Boolean expression. $f = (B + B C) (B + ¯ ¯¯ ¯ B C) (B + D)$ The minimum number of NAND-gates required to implement this function $^{'} f^{'}$ will be __________ 0

Discussion

15.	A small block is sliding on a frictionless inclined plane that is moving upward with a cons†an t acceleration a. If the block remains at a cons†an t height from ground, then the acceleration of the inclined plane (Acceleration due to gravity is g) is
Answer» A small block is sliding on a frictionless inclined plane that is moving upward with a cons†an t acceleration a. If the block remains at a cons†an t height from ground, then the acceleration of the inclined plane (Acceleration due to gravity is g) is

Discussion

16.	A body is attached to the lower end of a vertical spiral spring and it is gradually lowered to its equilibrium position. This stretches the spring by a length x. If the same body attached to the same spring is allowed to fall suddenly, what would be the maximum stretching in this case
Answer» A body is attached to the lower end of a vertical spiral spring and it is gradually lowered to its equilibrium position. This stretches the spring by a length x. If the same body attached to the same spring is allowed to fall suddenly, what would be the maximum stretching in this case

Discussion

17.	Ratio between potential energy, kinetic energy and total energy of electron in hydrogen atom are
Answer» Ratio between potential energy, kinetic energy and total energy of electron in hydrogen atom are

Discussion

18.	A uniform rod of mass M and length L is placed in a horizontal plane with one end hinged about the vertical axis. A horizontal force F=Mg2 is applied at a distance 5L6 from the hinged end. The angular acceleration of the rod will be
Answer» A uniform rod of mass M and length L is placed in a horizontal plane with one end hinged about the vertical axis. A horizontal force $F = \frac{M g}{2}$ is applied at a distance $\frac{5 L}{6}$ from the hinged end. The angular acceleration of the rod will be

Discussion

19.	An object is approaching towards a plane mirror with a cons†an t velocity v making an angle 45^° with the perpendicular line drawn on the surface of mirror. what will be the velocity of the image formed
Answer» An object is approaching towards a plane mirror with a cons†an t velocity v making an angle 45^° with the perpendicular line drawn on the surface of mirror. what will be the velocity of the image formed

Discussion

20.	what is the donor concentration in n-type germanium of 1ohm-cm resistivity at 300K given electron mobility is equals to 3900cm^{}/V.s
Answer» what is the donor concentration in n-type germanium of 1ohm-cm resistivity at 300K given electron mobility is equals to 3900cm^{}/V.s

Discussion

21.	A grasshopper can jump a maximum distance 1.6 m. It spends negligible time on the ground. How far can it go in 10 s?(Take g=10 m/s2)
Answer» A grasshopper can jump a maximum distance $1.6 m$ . It spends negligible time on the ground. How far can it go in $10 s$ ? (Take $g = 10 m / s^{2}$ )

Discussion

22.	The volume of a gas at 200∘C is 200 ml. If the temperature is reduced to −20∘C at constant pressure, its volume will be
Answer» The volume of a gas at $200^{\circ} C$ is 200 ml. If the temperature is reduced to $- 20^{\circ} C$ at constant pressure, its volume will be

22.

The volume of a gas at 200∘C is 200 ml. If the temperature is reduced to −20∘C at constant pressure, its volume will be

Answer»

The volume of a gas at $200^{\circ} C$ is 200 ml. If the temperature is reduced to $- 20^{\circ} C$ at constant pressure, its volume will be

Discussion

23.	An α−particle of energy 5 MeV is scattered through 180∘ by gold nucleus. The distance of closest approach is of the order of
Answer» An $α -$ particle of energy $5 M e V$ is scattered through $180^{\circ}$ by gold nucleus. The distance of closest approach is of the order of

Discussion

24.	An electric dipole consists of two chargesof 0.1 uC separated by a distance of 2.0 cm. The dipole isplaced in an external field of 10 NC. What maximumtorque does the field exert on the dipole?
Answer» An electric dipole consists of two chargesof 0.1 uC separated by a distance of 2.0 cm. The dipole isplaced in an external field of 10 NC. What maximumtorque does the field exert on the dipole?

Discussion

25.	A narrow monochromatic beam of light of intensity I is incident on a glass plate as shown in the figure. Another identical glass plate is kept close to the first one and parallel to it. Each glass plate reflects 25% of the light incident on it and transmits the remaining. The ratio √ImaxImin for the interference pattern formed by two beams obtained after one reflection at each plate is.
Answer» A narrow monochromatic beam of light of intensity $I$ is incident on a glass plate as shown in the figure. Another identical glass plate is kept close to the first one and parallel to it. Each glass plate reflects 25% of the light incident on it and transmits the remaining. The ratio $\sqrt{\frac{I_{max}}{I_{min}}}$ for the interference pattern formed by two beams obtained after one reflection at each plate is.

Discussion

26.	what is quantum mechanics and why was it developed ?
Answer» what is quantum mechanics and why was it developed ?

Discussion

27.	A bar magnet of magnetic moment 3.0 Am2 placed in a uniform magnetic induction field of 2×10-5 T . If each pole of the magnet experiences a force of 6 ×10-4 N , then what is the length of the magnet ?
Answer» A bar magnet of magnetic moment 3.0 Am²placed in a uniform magnetic induction field of 2×10^-5T . If each pole of the magnet experiences a force of 6 ×10^-4N , then what is the length of the magnet ?

Discussion

28.	A particle executes simple harmonic motion between x = -A and x=+ A. The time taken for it to go from the mean position, O to A2 is T1 and to go from A2 to A is T2. Then,
Answer» A particle executes simple harmonic motion between x = -A and x=+ A. The time taken for it to go from the mean position, O to $\frac{A}{2}$ is $T_{1}$ and to go from $\frac{A}{2}$ to A is $T_{2}$ . Then,

Discussion

29.	The numerical aperture of a microscope required to just resolve two points separated by a distance of 10−4 cm when wavelength of light is 5.8×10−5 cm is
Answer» The numerical aperture of a microscope required to just resolve two points separated by a distance of $10^{- 4} cm$ when wavelength of light is $5.8 \times 10^{- 5} cm$ is

Discussion

30.	a particle of mass m is attached to 3 springs a,b,c of equal spring cons†an ts k.the angle between the springs be 120 degrees with particle at its centre.if the particle is pushed against c and released.find the time period of oscillation
Answer» a particle of mass m is attached to 3 springs a,b,c of equal spring cons†an ts k.the angle between the springs be 120 degrees with particle at its centre.if the particle is pushed against c and released.find the time period of oscillation

Discussion

31.	what are the number of electrons protons and neutrons present in a alpha particle, beta particle, gamma particle, neutrino and antineutrino
Answer» what are the number of electrons protons and neutrons present in a alpha particle, beta particle, gamma particle, neutrino and antineutrino

Discussion

32.	59.Several cars are moving from town A to town B. Each car leaving from town A with speed 60 km p hr at and interval of 30 seconds. Due to bad weather conditions all cars slowed down to 40 km p hr simultaneously. Find the time interval the cars will enter town B.
Answer» 59.Several cars are moving from town A to town B. Each car leaving from town A with speed 60 km p hr at and interval of 30 seconds. Due to bad weather conditions all cars slowed down to 40 km p hr simultaneously. Find the time interval the cars will enter town B.

Discussion

33.	Which of the following is not optically active
Answer» Which of the following is not optically active

Discussion

34.	a charged conducting rod of charge Q and length L , a point charge q placed at a distance x from it . Determine net force on point charge .
Answer» a charged conducting rod of charge Q and length L , a point charge q placed at a distance x from it . Determine net force on point charge .

Discussion

35.	A man B standing on a cart throws a ball with speed 2 m/s w.r.t. himself. The cart is moving with a constant speed rightwards. At which angle with velocity of cart should the man B throw the ball relative to himself, such that the ball moves vertically up w.r.t. groundOptions:Should have chosen 150°30°60°120°
Answer» A man B standing on a cart throws a ball with speed 2 m/s w.r.t. himself. The cart is moving with a constant speed rightwards. At which angle with velocity of cart should the man B throw the ball relative to himself, such that the ball moves vertically up w.r.t. ground Options: Should have chosen 150° 30° 60° 120°

Discussion

36.	18.The length of an elastic string is x m when the tension is 8 N and y m when the tension is 10 N The length in metres when the tension is 18 N
Answer» 18.The length of an elastic string is x m when the tension is 8 N and y m when the tension is 10 N The length in metres when the tension is 18 N

Discussion

37.	What is the motion of pirate ride (Columbus boat) in amusement park
Answer» What is the motion of pirate ride (Columbus boat) in amusement park

Discussion

38.	29.Two diff. loops are concentric but perpendicular to each other . the current in one loop is clockwise and increasing with time .the induced current in other loop is ??
Answer» 29.Two diff. loops are concentric but perpendicular to each other . the current in one loop is clockwise and increasing with time .the induced current in other loop is ??

Discussion

39.	Can reflection of light be related to Newton's third law of motion, "Every action has an equal and opposite reaction" ?
Answer» Can reflection of light be related to Newton's third law of motion, "Every action has an equal and opposite reaction" ?

Discussion

40.	A long straight wire is parallel to one edge as in figure. If the current in the long wire varies with time as I=I0e−tτ, what will be the induced emf in the loop ?
Answer» A long straight wire is parallel to one edge as in figure. If the current in the long wire varies with time as $I = I_{0} e^{\frac{- t}{τ}},$ what will be the induced emf in the loop ?

Discussion

41.	If →A=^i−2^j, →B=2^i+3^k and →C=^i+^j, then component of (→A+→B) along →C will be
Answer» If $\to A =^i - 2^j, \to B = 2^i + 3^k$ and $\to C =^i +^j$ , then component of $(\to A + \to B)$ along $\to C$ will be

Discussion

42.	Two balls having masses m1=5 kg and m2=10 kg moving with velocities u1=10 m/s and u2=5 m/s collide elastically. Find the change in momentum of the ball having mass m1 due to collision
Answer» Two balls having masses $m_{1} = 5 kg$ and $m_{2} = 10 kg$ moving with velocities $u_{1} = 10 m/s$ and $u_{2} = 5 m/s$ collide elastically. Find the change in momentum of the ball having mass $m_{1}$ due to collision

Discussion

43.	Two cars A and B cross a point P with velocities 10/m and 15 m/s. After that, they move with different uniform accelerations and the car A overtakes B with a speed of 25 ms-1. What is velocity of B at that instant?
Answer» Two cars A and B cross a point P with velocities 10/m and 15 m/s. After that, they move with different uniform accelerations and the car A overtakes B with a speed of 25 ms^-1. What is velocity of B at that instant?

Discussion

44.	A particle of mass m and charge q moves with a constant velocity v along the positive x direction. It enters a region containing a uniform magnetic field of magnitude B directed along the negative z direction, extending from x= a to x= b . The minimum value of v required so that the particle can just enter the region x> b is
Answer» A particle of mass $m$ and charge $q$ moves with a constant velocity $v$ along the positive $x$ direction. It enters a region containing a uniform magnetic field of magnitude B directed along the negative z direction, extending from $x = a$ to $x = b$ . The minimum value of $v$ required so that the particle can just enter the region $x > b$ is

Discussion

45.	The ratio of diameters of two wires of same material is n:1. The length of wires are 4 m each. On applying the same load, the ratio of the increase in the length of thin wire to the thick wire will be
Answer» The ratio of diameters of two wires of same material is $n : 1$ . The length of wires are 4 m each. On applying the same load, the ratio of the increase in the length of thin wire to the thick wire will be

Discussion

46.	When a ball is h meter high from a point O, its velocity is v0. When it is h meter below O, its velocity is 2v0. Find the maximum height from O it will acquire
Answer» When a ball is $h$ meter high from a point $O$ , its velocity is $v_{0}$ . When it is $h$ meter below $O$ , its velocity is $2 v_{0}$ . Find the maximum height from $O$ it will acquire

Discussion

47.	The compression ratio of a gas power plant cycle corresponding to maximum work output for the givne temperature limits of Tmin and Tmax will be
Answer» The compression ratio of a gas power plant cycle corresponding to maximum work output for the givne temperature limits of $T_{m i n}$ and $T_{m a x}$ will be

Discussion

48.	A potential difference of 15000 V is applied across the ends of a copper target. The speed of the emitted X-Rays inside the tube is -Assume standard values.
Answer» A potential difference of $15000 V$ is applied across the ends of a copper target. The speed of the emitted X-Rays inside the tube is - Assume standard values.

Discussion

49.	An elevator is going up. The variation in the velocity of the elevator is as shown in the graph. What is the height to which the elevator takes the passengers?
Answer» An elevator is going up. The variation in the velocity of the elevator is as shown in the graph. What is the height to which the elevator takes the passengers?

Discussion

50.	A disc is suspended at a point R2 above its center, Find its period of oscillation.
Answer» A disc is suspended at a point $\frac{R}{2}$ above its center, Find its period of oscillation.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A diver at a depth of 12m in water sees the sky in a cone of semi vertical anglea) sin^-1(4/3) b) tan^-1(4/3) c) sin^-1(3/4) d) 90degrees

Why can we say that speed is equal to time upon length

Shown in the figure, is a conductor carrying current I. The net magnetic induction at the point O is given by xμ0Iθ24πR. Find the value of x.[Point O is the common center of all the three arcs.]

The value of sec(sec−15) is

A circuit contains an ammeter, a battery of 30 V and a resistance of 40.8 ohm all connected in series. If the ammeter has a coil of resistance 480 ohm and a shunt of resistance 20 ohm, the reading in the ammeter will be

a spring is loaded with two blocks of masses m1 and m2,where m1 is rigidly fixed with the spring and m2 is just kept on the block m1.the maximum energy of oscillation is possible for the system having the block m2 in contact with m1 is (1)m1^2g^2/2k (2)m2^2g^2/2k (3)(m1+m2)^2g^2/2k (4)none of these

77.An ammeter and a volt meter of resistance R are connected in series to an electric cell of negligible internal resistance.Their readings are A and V respectively.If another resistance R is connected in parallel with the voltmeter then

Why opposite signs are repelling each other in molecular bonding ?

A small body of mass 0.10 kg is executing S.H.M. of amplitude 1.0 m and period 0.20 sec. The maximum force acting on it is

An equiconvex lens has power P and radii of curvature R. The radius of curvature of the surface of a plano-convex lens made of the same material with power 1.5P is

Two particles A & B are projected with same speed at angles of projections (90 -a) & (90 -2a) .If their horizontal ranges are equal ,then value of 'a' is a) 15b) 30c)7.5d)22.5

In the given potentiometer circuit length of the wire AB is 3 m and resistance is R=4.5 Ω. The length AC for no deflection in galvanometer is

Consider a Boolean expression.f=(B+BC)(B+¯¯¯¯BC)(B+D)The minimum number of NAND-gates required to implement this function ′f′ will be __________0

A small block is sliding on a frictionless inclined plane that is moving upward with a cons†an t acceleration a. If the block remains at a cons†an t height from ground, then the acceleration of the inclined plane (Acceleration due to gravity is g) is

A body is attached to the lower end of a vertical spiral spring and it is gradually lowered to its equilibrium position. This stretches the spring by a length x. If the same body attached to the same spring is allowed to fall suddenly, what would be the maximum stretching in this case

Ratio between potential energy, kinetic energy and total energy of electron in hydrogen atom are

A uniform rod of mass M and length L is placed in a horizontal plane with one end hinged about the vertical axis. A horizontal force F=Mg2 is applied at a distance 5L6 from the hinged end. The angular acceleration of the rod will be

An object is approaching towards a plane mirror with a cons†an t velocity v making an angle 45^° with the perpendicular line drawn on the surface of mirror. what will be the velocity of the image formed

what is the donor concentration in n-type germanium of 1ohm-cm resistivity at 300K given electron mobility is equals to 3900cm^{}/V.s

A grasshopper can jump a maximum distance 1.6 m. It spends negligible time on the ground. How far can it go in 10 s?(Take g=10 m/s2)

The volume of a gas at 200∘C is 200 ml. If the temperature is reduced to −20∘C at constant pressure, its volume will be

An α−particle of energy 5 MeV is scattered through 180∘ by gold nucleus. The distance of closest approach is of the order of

An electric dipole consists of two chargesof 0.1 uC separated by a distance of 2.0 cm. The dipole isplaced in an external field of 10 NC. What maximumtorque does the field exert on the dipole?

what is quantum mechanics and why was it developed ?

A bar magnet of magnetic moment 3.0 Am2 placed in a uniform magnetic induction field of 2×10-5 T . If each pole of the magnet experiences a force of 6 ×10-4 N , then what is the length of the magnet ?

A particle executes simple harmonic motion between x = -A and x=+ A. The time taken for it to go from the mean position, O to A2 is T1 and to go from A2 to A is T2. Then,

The numerical aperture of a microscope required to just resolve two points separated by a distance of 10−4 cm when wavelength of light is 5.8×10−5 cm is

a particle of mass m is attached to 3 springs a,b,c of equal spring cons†an ts k.the angle between the springs be 120 degrees with particle at its centre.if the particle is pushed against c and released.find the time period of oscillation

what are the number of electrons protons and neutrons present in a alpha particle, beta particle, gamma particle, neutrino and antineutrino

59.Several cars are moving from town A to town B. Each car leaving from town A with speed 60 km p hr at and interval of 30 seconds. Due to bad weather conditions all cars slowed down to 40 km p hr simultaneously. Find the time interval the cars will enter town B.

Which of the following is not optically active

a charged conducting rod of charge Q and length L , a point charge q placed at a distance x from it . Determine net force on point charge .

18.The length of an elastic string is x m when the tension is 8 N and y m when the tension is 10 N The length in metres when the tension is 18 N

What is the motion of pirate ride (Columbus boat) in amusement park

29.Two diff. loops are concentric but perpendicular to each other . the current in one loop is clockwise and increasing with time .the induced current in other loop is ??

Can reflection of light be related to Newton's third law of motion, "Every action has an equal and opposite reaction" ?

A long straight wire is parallel to one edge as in figure. If the current in the long wire varies with time as I=I0e−tτ, what will be the induced emf in the loop ?

If →A=^i−2^j, →B=2^i+3^k and →C=^i+^j, then component of (→A+→B) along →C will be

Two balls having masses m1=5 kg and m2=10 kg moving with velocities u1=10 m/s and u2=5 m/s collide elastically. Find the change in momentum of the ball having mass m1 due to collision

Two cars A and B cross a point P with velocities 10/m and 15 m/s. After that, they move with different uniform accelerations and the car A overtakes B with a speed of 25 ms-1. What is velocity of B at that instant?

The ratio of diameters of two wires of same material is n:1. The length of wires are 4 m each. On applying the same load, the ratio of the increase in the length of thin wire to the thick wire will be

When a ball is h meter high from a point O, its velocity is v0. When it is h meter below O, its velocity is 2v0. Find the maximum height from O it will acquire

The compression ratio of a gas power plant cycle corresponding to maximum work output for the givne temperature limits of Tmin and Tmax will be

A potential difference of 15000 V is applied across the ends of a copper target. The speed of the emitted X-Rays inside the tube is -Assume standard values.

An elevator is going up. The variation in the velocity of the elevator is as shown in the graph. What is the height to which the elevator takes the passengers?

A disc is suspended at a point R2 above its center, Find its period of oscillation.