50278 + Interview Questions in Physics

1.	Motion is relative or absolute
Answer» Motion is relative or absolute

Discussion

2.	A particle is dropped from the top of the tower of height H. Distance travelled by the particle in last second is 35 m. Find the height of the tower. [Take g=10 m/s2]
Answer» A particle is dropped from the top of the tower of height $H$ . Distance travelled by the particle in last second is $35 m$ . Find the height of the tower. [Take $g = 10 {m/s}^{2}$ ]

Discussion

3.	Two wires of the same material and length are stretched by the same force. Their masses are in the ratio 3:2. Then, their elongations will be in the ratio :
Answer» Two wires of the same material and length are stretched by the same force. Their masses are in the ratio $3 : 2$ . Then, their elongations will be in the ratio :

Discussion

4.	A police inspector in a jeep is chasing a pickpocket on a straight road. The jeep is going at its maximum speed v (assume it to be uniform). The pickpocket rides on the motorcycle of a waiting friend. When the jeep is at a distance d away, and the motorcycle starts with a constant acceleration a. Show that the pickpocket will be caught if v≥√2ad.
Answer» A police inspector in a jeep is chasing a pickpocket on a straight road. The jeep is going at its maximum speed v (assume it to be uniform). The pickpocket rides on the motorcycle of a waiting friend. When the jeep is at a distance d away, and the motorcycle starts with a constant acceleration a. Show that the pickpocket will be caught if $v \geq \sqrt{2 a d}$ .

Discussion

5.	Substances which are attracted by external magnetic field are called
Answer» Substances which are attracted by external magnetic field are called

Discussion

6.	A stationary source emits sound of frequency f0=492 Hz. The sound is reflected by a large car approaching the source with a speed of 2 ms−1. The reflected signal is received by the source and superposed with the original. The beat frequency of the resulting signal is Hz. (Given that the speed of sound in air is 330 ms−1 and the car reflects the sound at the frequency it has received).
Answer» A stationary source emits sound of frequency $f_{0} = 492 H z$ . The sound is reflected by a large car approaching the source with a speed of $2 m s^{- 1}$ . The reflected signal is received by the source and superposed with the original. The beat frequency of the resulting signal is $H z$ . (Given that the speed of sound in air is $330 m s^{- 1}$ and the car reflects the sound at the frequency it has received).

Discussion

7.	If pulleys shown in the diagram are smooth and massless and a1 & a2 are acceleration of blocks of mass 4 kg and 8 kg respectively. Then find a2.
Answer» If pulleys shown in the diagram are smooth and massless and $a_{1}$ & $a_{2}$ are acceleration of blocks of mass $4 kg$ and $8 kg$ respectively. Then find $a_{2}$ .

Discussion

8.	n moles of a gas filled in a container is in thermodynamic equilibrium initially at temperature T. If the gas is compressed quasi-statically and isothermally to half its initial volume, the work done by the atmosphere on the piston is :
Answer» $n$ moles of a gas filled in a container is in thermodynamic equilibrium initially at temperature $T$ . If the gas is compressed quasi-statically and isothermally to half its initial volume, the work done by the atmosphere on the piston is :

Discussion

9.	If force, time and velocity are treated as fundamental quantities, then dimensional formula of energy will be
Answer» If force, time and velocity are treated as fundamental quantities, then dimensional formula of energy will be

Discussion

10.	A uniform circular disc of mass M and radius a is given. A part of the radius b is removed from it. The distance between centre of original disc and circular hole's centre is c. The new position of C.M. from O is:
Answer» A uniform circular disc of mass M and radius a is given. A part of the radius b is removed from it. The distance between centre of original disc and circular hole's centre is c. The new position of C.M. from O is:

Discussion

11.	In class, while teaching Huygens principle we were taught that a tertiary wavelet exist inner to the original wavefront. But while reading the text I got a notion that backwave doesn't exist. So does it really exist? If not, why doesn't it exist?
Answer» In class, while teaching Huygens principle we were taught that a tertiary wavelet exist inner to the original wavefront. But while reading the text I got a notion that backwave doesn't exist. So does it really exist? If not, why doesn't it exist?

Discussion

12.	A ball is thrown upward with an initial velocity of 100 ms−1. Find the height of the ball after 15 s. Take g=10 ms−2
Answer» A ball is thrown upward with an initial velocity of $100 {ms}^{- 1}$ . Find the height of the ball after $15 s$ . Take $g = 10 {ms}^{- 2}$

Discussion

13.	Acceleration of the particle in a rectilinear motion is given as a=2t−2 in (m/s2). The final position of the particle as a function of time t is (Given that at t=0,u=2 m/s,x=4 m)
Answer» Acceleration of the particle in a rectilinear motion is given as $a = 2 t - 2$ in $(m / s^{2})$ . The final position of the particle as a function of time $t$ is (Given that at $t = 0, u = 2 m / s, x = 4 m$ )

Discussion

14.	If surface tension of liquid is 0.03 N/m, then work done in formation of liquid drop of radius 1 cm is
Answer» If surface tension of liquid is $0.03 N/m$ , then work done in formation of liquid drop of radius $1 cm$ is

Discussion

15.	An ant moves from A to B then to c, what is the distance (d) and displacement (s) of the ant?
Answer» An ant moves from A to B then to c, what is the distance (d) and displacement (s) of the ant?

15.

An ant moves from A to B then to c, what is the distance (d) and displacement (s) of the ant?

Answer»

An ant moves from A to B then to c, what is the distance (d) and displacement (s) of the ant?

Discussion

16.	A body released from a great height falls freely towards the earth.Another body is released from the same height exactly one second later. The separation between both the bodies two seconds after the release of the second body is a) 24.5 metre b)34.5 metre c) 44.5 metre d) 54.5 metre
Answer» A body released from a great height falls freely towards the earth.Another body is released from the same height exactly one second later. The separation between both the bodies two seconds after the release of the second body is a) 24.5 metre b)34.5 metre c) 44.5 metre d) 54.5 metre

16.

A body released from a great height falls freely towards the earth.Another body is released from the same height exactly one second later. The separation between both the bodies two seconds after the release of the second body is a) 24.5 metre b)34.5 metre c) 44.5 metre d) 54.5 metre

Answer»

A body released from a great height falls freely towards the earth.Another body is released from the same height exactly one second later. The separation between both the bodies two seconds after the release of the second body is

a) 24.5 metre

b)34.5 metre

c) 44.5 metre

d) 54.5 metre

Discussion

17.	machine gun fires 10 bullets/s, each of mass 10g, the speed of each bullet is 20 cm/s, then force of recoil is:
Answer» machine gun fires 10 bullets/s, each of mass 10g, the speed of each bullet is 20 cm/s, then force of recoil is:

Discussion

18.	A body of mass 10kg is acted upon rest simultaneously by two forces 4N and 3N at right angle to each other. The kinetic energy of the body at the end of 10sec is A)100j B)300j C)50j D)125
Answer» A body of mass 10kg is acted upon rest simultaneously by two forces 4N and 3N at right angle to each other. The kinetic energy of the body at the end of 10sec is A)100j B)300j C)50j D)125

18.

A body of mass 10kg is acted upon rest simultaneously by two forces 4N and 3N at right angle to each other. The kinetic energy of the body at the end of 10sec is A)100j B)300j C)50j D)125

Answer»

A body of mass 10kg is acted upon rest simultaneously by two forces 4N and 3N at right angle to each other. The kinetic energy of the body at the end of 10sec is

A)100j

B)300j

C)50j

D)125

Discussion

19.	For polytropic process PVn = constant, Cm (molar heat capacity) of an ideal gas is given by
Answer» For polytropic process $P V^{n} = c o n s t a n t, C_{m}$ (molar heat capacity) of an ideal gas is given by

Discussion

20.	Two bodies of different masses ma and mb are dropped from two different heights, a and b respectively. The ratio of times taken by the two to drop through these distances is:
Answer» Two bodies of different masses $m_{a}$ and $m_{b}$ are dropped from two different heights, $a$ and $b$ respectively. The ratio of times taken by the two to drop through these distances is:

Discussion

21.	If →a,→b,→c are unit vectors such that →a+→b+→c=→0, then the value of →a⋅→b+→b⋅→c+→c⋅→a is equal to
Answer» If $\to a, \to b, \to c$ are unit vectors such that $\to a + \to b + \to c = \to 0,$ then the value of $\to a \cdot \to b + \to b \cdot \to c + \to c \cdot \to a$ is equal to

Discussion

22.	One mole of an ideal monatomic gas is taken along the process in which PVx=constant. The graph shown represents the variation of molar heat capacity of such a gas with respect to x . Find the values of C′ and x′ indicated in the diagram.
Answer» One mole of an ideal monatomic gas is taken along the process in which $P V^{x} = constant$ . The graph shown represents the variation of molar heat capacity of such a gas with respect to $x$ . Find the values of $C^{'}$ and $x^{'}$ indicated in the diagram.

Discussion

23.	A silver sphere of radius 1 cm and work function 4.7 eV is suspended from an insulating thread in a free space. It is under continuous illumination of 200 nm wavelength light. As photoelectrons are emitted, the sphere gets charged and acquires a potential. The maximum number of photoelectrons emitted from the sphere is A x 10z (where 1 < A < 10). The value of "Z" is___?
Answer» A silver sphere of radius 1 cm and work function 4.7 eV is suspended from an insulating thread in a free space. It is under continuous illumination of 200 nm wavelength light. As photoelectrons are emitted, the sphere gets charged and acquires a potential. The maximum number of photoelectrons emitted from the sphere is A x $10^{z}$ (where 1 < A < 10). The value of "Z" is___?

Discussion

24.	A car moves 100 m due east and then 25 due West (a )What is the distance covered by the car (b)What is the displacement
Answer» A car moves 100 m due east and then 25 due West (a )What is the distance covered by the car (b)What is the displacement

Discussion

25.	If a particle is projected from origin and it follows the trajectory y=x−12x2, then the time of flight is (g = acceleration due to gravity)
Answer» If a particle is projected from origin and it follows the trajectory $y = x - \frac{1}{2} x^{2}$ , then the time of flight is ( $g$ = acceleration due to gravity)

Discussion

26.	A logic gate is an electronic circuit which
Answer» A logic gate is an electronic circuit which

Discussion

27.	A machine gun fires 200 bullets per minute with a velocity of 60 m/s. What is the power of the machine gun, given that the mass of each bullet is 0.05 g?
Answer» A machine gun fires 200 bullets per minute with a velocity of 60 m/s. What is the power of the machine gun, given that the mass of each bullet is 0.05 g?

Discussion

28.	A ladder of mass M and length L is supported in equilibrium against a smooth vertical wall and a rough horizontal surface, as shown in figure. If the angle of inclination of the rod with the horizontal, then Determine the co-efficient of friction between ladder and horizontal surface.
Answer» A ladder of mass M and length L is supported in equilibrium against a smooth vertical wall and a rough horizontal surface, as shown in figure. If the angle of inclination of the rod with the horizontal, then Determine the co-efficient of friction between ladder and horizontal surface.

28.

A ladder of mass M and length L is supported in equilibrium against a smooth vertical wall and a rough horizontal surface, as shown in figure. If the angle of inclination of the rod with the horizontal, then Determine the co-efficient of friction between ladder and horizontal surface.

Answer»

A ladder of mass M and length L is supported in equilibrium against a smooth vertical wall and a rough horizontal surface, as shown in figure. If the angle of inclination of the rod with the horizontal, then

Determine the co-efficient of friction between ladder and horizontal surface.

Discussion

29.	Two vibrating strings are of same material but lengths l, 2l and radii 2r, r respectively are stretched under the same tension. Both are vibrating in their fundamental modes. The experimental arrangement is such that first string has both ends fixed, second string vibrates with one end fixed and other end as free. If the frequencies of vibration of first and second wire are n1 and n2, then n1n2= ________
Answer» Two vibrating strings are of same material but lengths l, 2l and radii 2r, r respectively are stretched under the same tension. Both are vibrating in their fundamental modes. The experimental arrangement is such that first string has both ends fixed, second string vibrates with one end fixed and other end as free. If the frequencies of vibration of first and second wire are $n_{1}$ and $n_{2}$ , then $\frac{n_{1}}{n_{2}}$ = ________

29.

Two vibrating strings are of same material but lengths l, 2l and radii 2r, r respectively are stretched under the same tension. Both are vibrating in their fundamental modes. The experimental arrangement is such that first string has both ends fixed, second string vibrates with one end fixed and other end as free. If the frequencies of vibration of first and second wire are n1 and n2, then n1n2= ________

Answer»

Two vibrating strings are of same material but lengths l, 2l and radii 2r, r respectively are stretched under the same tension. Both are vibrating in their fundamental modes. The experimental arrangement is such that first string has both ends fixed, second string vibrates with one end fixed and other end as free.

If the frequencies of vibration of first and second wire are $n_{1}$ and $n_{2}$ , then $\frac{n_{1}}{n_{2}}$ = ________

Discussion

30.	A car accelerates from rest with a constant acceleration α on a straight road. After gaining a velocity v, the car moves with the same velocity for some time. Then the car is decelerated to rest with a retardation β. If the total distance covered by the car is equal to S, the total time taken for its motion is
Answer» A car accelerates from rest with a constant acceleration $α$ on a straight road. After gaining a velocity $v$ , the car moves with the same velocity for some time. Then the car is decelerated to rest with a retardation $β$ . If the total distance covered by the car is equal to $S$ , the total time taken for its motion is

Discussion

31.	At Deoprayag (Garhwal, UP) river Alaknanada mixes with the river Bhagirathi and becomes river Ganga. Suppose Alaknanda has a width of 12 m, Bhagirathi has a width of 8 m and Ganga has a width of 16 m. Assume that the depth of water is same in the three rivers. Let the average speed of water in Alaknanda be 20 km h−1 and in Bhagirathi be 16 km h−1. Find the average speed of water in the river Ganga.
Answer» At Deoprayag (Garhwal, UP) river Alaknanada mixes with the river Bhagirathi and becomes river Ganga. Suppose Alaknanda has a width of 12 m, Bhagirathi has a width of 8 m and Ganga has a width of 16 m. Assume that the depth of water is same in the three rivers. Let the average speed of water in Alaknanda be 20 km $h^{- 1}$ and in Bhagirathi be 16 km $h^{- 1}$ . Find the average speed of water in the river Ganga.

Discussion

32.	Some liquid is filled in a cylindrical vessel of radius R. Let F1 be the force applied by the liquid on the bottom of the cylinder. Now the same liquid is poured into a vessel of uniform square cross-section of side R. Let F2 be the force applied by the liquid on the bottom of this new vessel. Then:
Answer» Some liquid is filled in a cylindrical vessel of radius $R$ . Let $F_{1}$ be the force applied by the liquid on the bottom of the cylinder. Now the same liquid is poured into a vessel of uniform square cross-section of side $R$ . Let $F_{2}$ be the force applied by the liquid on the bottom of this new vessel. Then:

Discussion

33.	A single conservative force F(x) acts on 1 kg particle that moves along x axis. The potential energy U(x) is given by U(x)=10+(x−1)2. At x=2 m, The particle has kinetic energy of 20 J. The maximum kinetic energy of the particle is
Answer» A single conservative force $F (x)$ acts on $1 kg$ particle that moves along $x$ axis. The potential energy $U (x)$ is given by $U (x) = 10 + (x - 1)^{2}$ . At $x = 2 m$ , The particle has kinetic energy of $20 J$ . The maximum kinetic energy of the particle is

Discussion

34.	A microscope is focused on an ink mark on the top of a table. If we place a glass slab 3cm thick on it, how should the microscope be moved to focus the ink spot again? The refractive index of glass slab is 1.5 cm.
Answer» A microscope is focused on an ink mark on the top of a table. If we place a glass slab 3cm thick on it, how should the microscope be moved to focus the ink spot again? The refractive index of glass slab is 1.5 cm.

Discussion

35.	Which of the following particles will have same frequency of revolution when projected with same velocity perpendicular to a magnetic field? 1) Li++ 2) He++ 3) Proton 4) Deuteron
Answer» Which of the following particles will have same frequency of revolution when projected with same velocity perpendicular to a magnetic field? 1) $L i^{+ +}$ 2) $H e^{+ +}$ 3) $P r o t o n$ 4) $D e u t e r o n$

Discussion

36.	Explain why transformer is the most efficient electrical machine?
Answer» Explain why transformer is the most efficient electrical machine?

Discussion

37.	∫(t√t+√tt2)dt is equal to
Answer» $\int (\frac{t \sqrt{t} + \sqrt{t}}{t^{2}}) d t$ is equal to

Discussion

38.	The values of maximum current and impedance in the given circuit are
Answer» The values of maximum current and impedance in the given circuit are

Discussion

39.	The force F1 that is necessary to move a body up an inclined plane is double the force F2 that is necessary to just prevent it from sliding down, then: ( Given that ϕ is angle of repose, θ is angle of inclined plane and w is weight of the body)
Answer» The force $F_{1}$ that is necessary to move a body up an inclined plane is double the force $F_{2}$ that is necessary to just prevent it from sliding down, then: ( Given that $ϕ$ is angle of repose, $θ$ is angle of inclined plane and $w$ is weight of the body)

Discussion

40.	A non-conducting ring of radius R has charge Q distributed over it. If it rotates with an angular velocity ω about its axis, the equivalent electric current will be
Answer» A non-conducting ring of radius R has charge Q distributed over it. If it rotates with an angular velocity $ω$ about its axis, the equivalent electric current will be

Discussion

41.	Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d):
Answer» Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d):

41.

Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d):

Answer»

Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d):

Discussion

42.	The ratio of the electric field at a point R2 inside a uniformly charged shell to a point R2 outside the same shell is
Answer» The ratio of the electric field at a point $\frac{R}{2}$ inside a uniformly charged shell to a point $\frac{R}{2}$ outside the same shell is

Discussion

43.	A ball is projected upwards from the foot of a tower. The ball crosses the top of the tower twice after an interval of 6 s and the ball reaches the ground after 12 s. The height of the tower is (g=10 m/s2)
Answer» A ball is projected upwards from the foot of a tower. The ball crosses the top of the tower twice after an interval of $6 s$ and the ball reaches the ground after $12 s$ . The height of the tower is $(g = 10 m / s^{2})$

Discussion

44.	From the figure describing photoelectric effect, we may infer correctly that
Answer» From the figure describing photoelectric effect, we may infer correctly that

44.

From the figure describing photoelectric effect, we may infer correctly that

Answer»

From the figure describing photoelectric effect, we may infer correctly that

Discussion

45.	Find the angular frequency of a mass attached to a spring, kept on a horizontal frictionless surface.
Answer» Find the angular frequency of a mass attached to a spring, kept on a horizontal frictionless surface.

Discussion

46.	A particle is projected along the inner surface of a smooth vertical circle of radius R, its velocity at the lowest point being √95Rg5. It will leave the circle at an angular distance of______from the vertical line joining highest and lowest points.
Answer» A particle is projected along the inner surface of a smooth vertical circle of radius $R$ , its velocity at the lowest point being $\frac{\sqrt{95 R g}}{5}$ . It will leave the circle at an angular distance of______from the vertical line joining highest and lowest points.

Discussion

47.	A ring consisting of two parts ADB and ACB of same conductivity k carries a net amount of heat H. The ADB part is now replaced with another metal keeping the temperatures T1 and T2 constant. The net heat carried increases to 2H. What should be the conductivity of the new ADB part? Given ACBADB=3 :
Answer» A ring consisting of two parts ADB and ACB of same conductivity k carries a net amount of heat H. The ADB part is now replaced with another metal keeping the temperatures $T_{1} a n d T_{2}$ constant. The net heat carried increases to 2H. What should be the conductivity of the new ADB part? Given $\frac{A C B}{A D B} = 3$ :

Discussion

48.	A cup of tea cools from 80∘ C to 60∘ C in one minute. The ambient temperature is 30∘ C. In coolingfrom 60∘ C to 50∘ C it will take nearly
Answer» A cup of tea cools from $80^{\circ} C$ to $60^{\circ} C$ in one minute. The ambient temperature is $30^{\circ} C$ . In coolingfrom $60^{\circ} C$ to $50^{\circ} C i t w i l l t a k e n e a r l y$

48.

A cup of tea cools from 80∘ C to 60∘ C in one minute. The ambient temperature is 30∘ C. In coolingfrom 60∘ C to 50∘ C it will take nearly

Answer»

A cup of tea cools from $80^{\circ} C$ to $60^{\circ} C$ in one minute.

The ambient temperature is $30^{\circ} C$ .

In coolingfrom $60^{\circ} C$ to $50^{\circ} C i t w i l l t a k e n e a r l y$

Discussion

49.	The displacement, y of a particle on a straight line is given by y=f(x,t), as a function of time. Which of the following functions does not represent wave motion?
Answer» The displacement, $y$ of a particle on a straight line is given by $y = f (x, t)$ , as a function of time. Which of the following functions does not represent wave motion?

Discussion

50.	A car is moving with a velocity of 20 m/sec. The driver sees a stationary truck at a distance of 100 m ahead. After some reaction time Δt he applies the brakes, produces a retardation of 4 m/s2. The maximum reaction time to avoid collision will be
Answer» A car is moving with a velocity of $20 m/sec$ . The driver sees a stationary truck at a distance of $100 m$ ahead. After some reaction time $Δ t$ he applies the brakes, produces a retardation of $4 {m/s}^{2}$ . The maximum reaction time to avoid collision will be

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Motion is relative or absolute

A particle is dropped from the top of the tower of height H. Distance travelled by the particle in last second is 35 m. Find the height of the tower. [Take g=10 m/s2]

Two wires of the same material and length are stretched by the same force. Their masses are in the ratio 3:2. Then, their elongations will be in the ratio :

Substances which are attracted by external magnetic field are called

If pulleys shown in the diagram are smooth and massless and a1 &amp; a2 are acceleration of blocks of mass 4 kg and 8 kg respectively. Then find a2.

n moles of a gas filled in a container is in thermodynamic equilibrium initially at temperature T. If the gas is compressed quasi-statically and isothermally to half its initial volume, the work done by the atmosphere on the piston is :

If force, time and velocity are treated as fundamental quantities, then dimensional formula of energy will be

A uniform circular disc of mass M and radius a is given. A part of the radius b is removed from it. The distance between centre of original disc and circular hole's centre is c. The new position of C.M. from O is:

In class, while teaching Huygens principle we were taught that a tertiary wavelet exist inner to the original wavefront. But while reading the text I got a notion that backwave doesn't exist. So does it really exist? If not, why doesn't it exist?

A ball is thrown upward with an initial velocity of 100 ms−1. Find the height of the ball after 15 s. Take g=10 ms−2

Acceleration of the particle in a rectilinear motion is given as a=2t−2 in (m/s2). The final position of the particle as a function of time t is (Given that at t=0,u=2 m/s,x=4 m)

If surface tension of liquid is 0.03 N/m, then work done in formation of liquid drop of radius 1 cm is

An ant moves from A to B then to c, what is the distance (d) and displacement (s) of the ant?

A body released from a great height falls freely towards the earth.Another body is released from the same height exactly one second later. The separation between both the bodies two seconds after the release of the second body is a) 24.5 metre b)34.5 metre c) 44.5 metre d) 54.5 metre

machine gun fires 10 bullets/s, each of mass 10g, the speed of each bullet is 20 cm/s, then force of recoil is:

A body of mass 10kg is acted upon rest simultaneously by two forces 4N and 3N at right angle to each other. The kinetic energy of the body at the end of 10sec is A)100j B)300j C)50j D)125

For polytropic process PVn = constant, Cm (molar heat capacity) of an ideal gas is given by

Two bodies of different masses ma and mb are dropped from two different heights, a and b respectively. The ratio of times taken by the two to drop through these distances is:

If →a,→b,→c are unit vectors such that →a+→b+→c=→0, then the value of →a⋅→b+→b⋅→c+→c⋅→a is equal to

One mole of an ideal monatomic gas is taken along the process in which PVx=constant. The graph shown represents the variation of molar heat capacity of such a gas with respect to x . Find the values of C′ and x′ indicated in the diagram.

A car moves 100 m due east and then 25 due West (a )What is the distance covered by the car (b)What is the displacement

If a particle is projected from origin and it follows the trajectory y=x−12x2, then the time of flight is (g = acceleration due to gravity)

A logic gate is an electronic circuit which

A machine gun fires 200 bullets per minute with a velocity of 60 m/s. What is the power of the machine gun, given that the mass of each bullet is 0.05 g?

A ladder of mass M and length L is supported in equilibrium against a smooth vertical wall and a rough horizontal surface, as shown in figure. If the angle of inclination of the rod with the horizontal, then Determine the co-efficient of friction between ladder and horizontal surface.

A single conservative force F(x) acts on 1 kg particle that moves along x axis. The potential energy U(x) is given by U(x)=10+(x−1)2. At x=2 m, The particle has kinetic energy of 20 J. The maximum kinetic energy of the particle is

A microscope is focused on an ink mark on the top of a table. If we place a glass slab 3cm thick on it, how should the microscope be moved to focus the ink spot again? The refractive index of glass slab is 1.5 cm.

Which of the following particles will have same frequency of revolution when projected with same velocity perpendicular to a magnetic field? 1) Li++ 2) He++ 3) Proton 4) Deuteron

Explain why transformer is the most efficient electrical machine?

∫(t√t+√tt2)dt is equal to

The values of maximum current and impedance in the given circuit are

The force F1 that is necessary to move a body up an inclined plane is double the force F2 that is necessary to just prevent it from sliding down, then: ( Given that ϕ is angle of repose, θ is angle of inclined plane and w is weight of the body)

A non-conducting ring of radius R has charge Q distributed over it. If it rotates with an angular velocity ω about its axis, the equivalent electric current will be

Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d):

The ratio of the electric field at a point R2 inside a uniformly charged shell to a point R2 outside the same shell is

A ball is projected upwards from the foot of a tower. The ball crosses the top of the tower twice after an interval of 6 s and the ball reaches the ground after 12 s. The height of the tower is (g=10 m/s2)

From the figure describing photoelectric effect, we may infer correctly that

Find the angular frequency of a mass attached to a spring, kept on a horizontal frictionless surface.

A particle is projected along the inner surface of a smooth vertical circle of radius R, its velocity at the lowest point being √95Rg5. It will leave the circle at an angular distance of______from the vertical line joining highest and lowest points.

A ring consisting of two parts ADB and ACB of same conductivity k carries a net amount of heat H. The ADB part is now replaced with another metal keeping the temperatures T1 and T2 constant. The net heat carried increases to 2H. What should be the conductivity of the new ADB part? Given ACBADB=3 :

A cup of tea cools from 80∘ C to 60∘ C in one minute. The ambient temperature is 30∘ C. In coolingfrom 60∘ C to 50∘ C it will take nearly

The displacement, y of a particle on a straight line is given by y=f(x,t), as a function of time. Which of the following functions does not represent wave motion?

A car is moving with a velocity of 20 m/sec. The driver sees a stationary truck at a distance of 100 m ahead. After some reaction time Δt he applies the brakes, produces a retardation of 4 m/s2. The maximum reaction time to avoid collision will be

If pulleys shown in the diagram are smooth and massless and a1 & a2 are acceleration of blocks of mass 4 kg and 8 kg respectively. Then find a2.