50278 + Interview Questions in Physics

1.	A particle with mass m is held in circular orbit around the origin by an attractive force F(r)=-Dr; where D is a positive constant. Assume that the Bohr model idea that ,the angular momentum is quantized i.e. it takes only integral multiples of h2π holds. The value of nth orbital radius is
Answer» A particle with mass m is held in circular orbit around the origin by an attractive force F(r)=-Dr; where D is a positive constant. Assume that the Bohr model idea that ,the angular momentum is quantized i.e. it takes only integral multiples of $\frac{h}{2 π}$ holds. The value of $n^{t h}$ orbital radius is

Discussion

2.	A table with smooth horizontal surface is fixed in a cabin that rotates with a uniform angular velocity ω in a circular path of radius R (figure 7-E3). A smooth groove AB of length L(<<R) is made on the surface of the table. The groove makes an angle ω with the radius OA of the circle in which the cabin rotates. A small particle is kept at the point A in the groove and is released to move along AB. Find the time taken by the particle to reach the point B.
Answer» A table with smooth horizontal surface is fixed in a cabin that rotates with a uniform angular velocity $ω$ in a circular path of radius R (figure 7-E3). A smooth groove AB of length L(<<R) is made on the surface of the table. The groove makes an angle $ω$ with the radius OA of the circle in which the cabin rotates. A small particle is kept at the point A in the groove and is released to move along AB. Find the time taken by the particle to reach the point B.

2.

A table with smooth horizontal surface is fixed in a cabin that rotates with a uniform angular velocity ω in a circular path of radius R (figure 7-E3). A smooth groove AB of length L(<<R) is made on the surface of the table. The groove makes an angle ω with the radius OA of the circle in which the cabin rotates. A small particle is kept at the point A in the groove and is released to move along AB. Find the time taken by the particle to reach the point B.

Answer»

A table with smooth horizontal surface is fixed in a cabin that rotates with a uniform angular velocity $ω$ in a circular path of radius R (figure 7-E3). A smooth groove AB of length L(<<R) is made on the surface of the table. The groove makes an angle $ω$ with the radius OA of the circle in which the cabin rotates. A small particle is kept at the point A in the groove and is released to move along AB. Find the time taken by the particle to reach the point B.

Discussion

3.	An electron enters the region between the plates of a parallel-plate capacitor with same initial velocity at an angle θ to the plants. The plate width is l and the plate separation is d. The electron follows the path shown, just missing the upper plate. Neglect gravity. Then,
Answer» An electron enters the region between the plates of a parallel-plate capacitor with same initial velocity at an angle $θ$ to the plants. The plate width is l and the plate separation is d. The electron follows the path shown, just missing the upper plate. Neglect gravity. Then,

Discussion

4.	How much work must be done to pull apart the electron and the proton that make up the Hydrogen atom, if the atom is initially in the state with n = 2
Answer» How much work must be done to pull apart the electron and the proton that make up the Hydrogen atom, if the atom is initially in the state with n = 2

Discussion

5.	A source of sound S moving with constant speed approaches a junction A. If the original frequency produced by the source is 640 Hz then for the situation shown in the figure, the apparent frequency heard by the observer at rest at O will be [speed of sound =340 m/s]
Answer» A source of sound $S$ moving with constant speed approaches a junction $A$ . If the original frequency produced by the source is $640 Hz$ then for the situation shown in the figure, the apparent frequency heard by the observer at rest at $O$ will be [speed of sound $= 340 m/s$ ]

Discussion

6.	[MP PET 1992]
Answer» [MP PET 1992]

6.

[MP PET 1992]

Answer»

[MP PET 1992]

Discussion

7.	Two different liquids are flowing in two tubes of equal radius. The ratio of coefficients of viscosity of liquids is 52:49 and the ratio of their densities is 13:1, then the ratio of their critical velocities will be
Answer» Two different liquids are flowing in two tubes of equal radius. The ratio of coefficients of viscosity of liquids is 52:49 and the ratio of their densities is 13:1, then the ratio of their critical velocities will be

Discussion

8.	What happens to the motion of any body after a particular time, when the directions of its velocity and acceleration are opposite to each other?
Answer» What happens to the motion of any body after a particular time, when the directions of its velocity and acceleration are opposite to each other?

Discussion

9.	A body falls freely from the top of a tower. It covers 36% of the total height in the last second before striking the ground level. The height of the tower is
Answer» A body falls freely from the top of a tower. It covers $36$ % of the total height in the last second before striking the ground level. The height of the tower is

Discussion

10.	A uniformly wound solenoidal coil of self-inductance 1.8×10−4 henry and resistance 6 ohm is broken up into two coils having lengths in the ratio 1 : 2. These identical coils are then connected in parallel across a 12 volt battery of negligible resistance. The steady state current through the battery is___ ampere.
Answer» A uniformly wound solenoidal coil of self-inductance $1.8 \times 10^{- 4}$ henry and resistance 6 ohm is broken up into two coils having lengths in the ratio 1 : 2. These identical coils are then connected in parallel across a 12 volt battery of negligible resistance. The steady state current through the battery is___ ampere.

Discussion

11.	An enemy plane is flying horizontally at an altitude of 2 km with a speed of 300 ms−1. An armyman with an anti-aircraft gun on the ground sights the enemy plane when it is directly overhead and fires a shell with a muzzle speed of 600 ms−1. At what angle with the vertical should the gun be fired so as to hit the plane?
Answer» An enemy plane is flying horizontally at an altitude of 2 km with a speed of 300 $m s^{- 1} .$ An armyman with an anti-aircraft gun on the ground sights the enemy plane when it is directly overhead and fires a shell with a muzzle speed of 600 $m s^{- 1}$ . At what angle with the vertical should the gun be fired so as to hit the plane?

Discussion

12.	A sample of radioactive material has a mass m, decay constant λ and molecular weight M. If NA is Avogadro's number, the initial activity of the sample is:
Answer» A sample of radioactive material has a mass m, decay constant λ and molecular weight M. If $N_{A}$ is Avogadro's number, the initial activity of the sample is:

Discussion

13.	A fixed ring of mass m has two beads A, B of mass m each; both being able to slide on the ring without friction. Initially the ring lies on a frictionless horizontal table and the beads are given velocities ν0 , relative to the ring, in the same direction. The initial relative acceleration of one of the beads with respect to the other is
Answer» A fixed ring of mass m has two beads A, B of mass m each; both being able to slide on the ring without friction. Initially the ring lies on a frictionless horizontal table and the beads are given velocities $ν_{0}$ , relative to the ring, in the same direction. The initial relative acceleration of one of the beads with respect to the other is

Discussion

14.	Block of mass 3 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in ms−2 at t = 0. (Take g=10ms−2
Answer» Block of mass 3 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in $m s^{- 2}$ at t = 0. (Take $g = 10 m s^{- 2}$

14.

Block of mass 3 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in ms−2 at t = 0. (Take g=10ms−2

Answer»

Block of mass 3 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in $m s^{- 2}$ at t = 0. (Take $g = 10 m s^{- 2}$

Discussion

15.	A ring of mass ‘m’ and radius ‘R’ rolls on a horizontal rough surface without slipping due to an applied force ‘F’. The friction force acting on the ring is
Answer» A ring of mass ‘m’ and radius ‘R’ rolls on a horizontal rough surface without slipping due to an applied force ‘F’. The friction force acting on the ring is

Discussion

16.	An ideal gas undergoes a process AB as shown in figure. Which of the following is true for the gas?
Answer» An ideal gas undergoes a process AB as shown in figure. Which of the following is true for the gas?

16.

An ideal gas undergoes a process AB as shown in figure. Which of the following is true for the gas?

Answer»

An ideal gas undergoes a process AB as shown in figure. Which of the following is true for the gas?

Discussion

17.	A stone weighing 1 kg is whirled in a vertical circle at the end of a rope of length 0.5 m. Stone completes the vertical circle with minimum possible speed. The velocity of the stone midway, when the string is horizontal is (Take g=10 m/s2)
Answer» A stone weighing $1 kg$ is whirled in a vertical circle at the end of a rope of length $0.5 m$ . Stone completes the vertical circle with minimum possible speed. The velocity of the stone midway, when the string is horizontal is (Take $g = 10 {m/s}^{2})$

Discussion

18.	The moon takes about 27.3 days to revolve round the earth in a nearly circular orbit of radius 3.84×105 km. Calculate the mass of the earth from these data.
Answer» The moon takes about 27.3 days to revolve round the earth in a nearly circular orbit of radius $3.84 \times 10^{5}$ km. Calculate the mass of the earth from these data.

Discussion

19.	Coil of 800 turns of effective area 0.05 m2 is kept perpendicular to a magnetic field of magnitude 5×10−5 T. When the plane of the coil is rotated by 90°around any of its coplanar axis in 0.1 s, the emf induced in the coil will be
Answer» Coil of 800 turns of effective area $0.05 m^{2}$ is kept perpendicular to a magnetic field of magnitude $5 \times 10^{- 5} T$ . When the plane of the coil is rotated by $90 °$ around any of its coplanar axis in $0.1 s$ , the emf induced in the coil will be

Discussion

20.	A metallic sphere floats in an immiscible mixture of water and a liquid such that its 45th volume is in water and 15th volume is in the liquid. Then, density of the metal is
Answer» A metallic sphere floats in an immiscible mixture of water and a liquid such that its $\frac{4}{5} th$ volume is in water and $\frac{1}{5} th$ volume is in the liquid. Then, density of the metal is

Discussion

21.	A long U tube is filled with a liquid of density ‘ρ ’ such that length of the tube above liquid is ‘a’ in both arm. One side of tube (right arm) is sealed and the tube is inverted (‘P0’ atmospheric pressure).
Answer» A long U tube is filled with a liquid of density ‘ $ρ$ ’ such that length of the tube above liquid is ‘a’ in both arm. One side of tube (right arm) is sealed and the tube is inverted (‘ $P_{0}$ ’ atmospheric pressure).

21.

A long U tube is filled with a liquid of density ‘ρ ’ such that length of the tube above liquid is ‘a’ in both arm. One side of tube (right arm) is sealed and the tube is inverted (‘P0’ atmospheric pressure).

Answer»

A long U tube is filled with a liquid of density ‘ $ρ$ ’ such that length of the tube above liquid is ‘a’ in both arm. One side of tube (right arm) is sealed and the tube is inverted (‘ $P_{0}$ ’ atmospheric pressure).

Discussion

22.	The angle of a prism is A and one of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the second (silvered) surface The refractive index of the material of the prism is
Answer» The angle of a prism is A and one of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the second (silvered) surface The refractive index of the material of the prism is

Discussion

23.	The figure shows two blocks of masses 6 kg and 4 kg placed on a frictionless surface and connected with spring. An external kick gives a velocity 15 m/s to 6 kg block and 10 m/s to 4 kg block in the opposite direction as shown. Find the velocity gain by the centre of mass of the system.
Answer» The figure shows two blocks of masses $6 kg$ and $4 kg$ placed on a frictionless surface and connected with spring. An external kick gives a velocity $15 m/s$ to $6 kg$ block and $10 m/s$ to $4 kg$ block in the opposite direction as shown. Find the velocity gain by the centre of mass of the system.

Discussion

24.	An object of specific gravity ρ is hung from a thin steel wire. The fundamental frequency (in Hz) is 300 Hz. The object is immersed in water with specific gravity ρw, so that one half its volume is submerged. The new fundamental frequency (in Hz) is
Answer» An object of specific gravity $ρ$ is hung from a thin steel wire. The fundamental frequency (in $H z$ ) is $300 H z$ . The object is immersed in water with specific gravity $ρ_{w}$ , so that one half its volume is submerged. The new fundamental frequency (in $H z$ ) is

Discussion

25.	The force vs displacement graph of a moving body is as shown in the figure. What is the work done as the body moves from x=5 m to x=35 m?
Answer» The force vs displacement graph of a moving body is as shown in the figure. What is the work done as the body moves from $x = 5 m$ to $x = 35 m$ ?

Discussion

26.	a ball thrown vertically upward with a velocity u it takes t0 seconds to reach the highest point the distance travelled in the last t seconds of its ascend( t < t0 second)?
Answer» a ball thrown vertically upward with a velocity u it takes t₀ seconds to reach the highest point the distance travelled in the last t seconds of its ascend( t < t₀second)?

Discussion

27.	Two blocks of masses 4 kg and 2 kg are placed on a frictionless surface and connected by a spring. An external kick gives a velocity of 12 m/s to the heavier block in the direction towards the lighter one. The magnitude of the velocities of two blocks in the center of mass frame, after the kick, are respectively
Answer» Two blocks of masses $4 kg$ and $2 kg$ are placed on a frictionless surface and connected by a spring. An external kick gives a velocity of $12 m/s$ to the heavier block in the direction towards the lighter one. The magnitude of the velocities of two blocks in the center of mass frame, after the kick, are respectively

Discussion

28.	The potential energy for a force field →F is given by U(x,y)=cos(x+y). The force acting on a particle at the position given by coordinates (0,π4) is
Answer» The potential energy for a force field $\to F$ is given by $U (x, y) = cos (x + y)$ . The force acting on a particle at the position given by coordinates $(0, \frac{π}{4})$ is

Discussion

29.	A Carnot engine takes 3×10^6cal of heat from a Reservoir at 627°cand gives to async at 27 °c the work done by the engine is
Answer» A Carnot engine takes 3×10^6cal of heat from a Reservoir at 627°cand gives to async at 27 °c the work done by the engine is

Discussion

30.	When a ceiling fan is switched on it starts from rest, while completing the 10th revolution it has angular velocity of 40 rad/s , find the angular acceleration of the fan ? (Assume uniform angular acceleration)
Answer» When a ceiling fan is switched on it starts from rest, while completing the $10^{t h}$ revolution it has angular velocity of $40 rad/s$ , find the angular acceleration of the fan ? (Assume uniform angular acceleration)

Discussion

31.	What is meant by dimensionless quantity?
Answer» What is meant by dimensionless quantity?

Discussion

32.	The total vibrational energy of a particle in SHM is E. Its kinetic energy at half the amplitude from mean position will be :
Answer» The total vibrational energy of a particle in $SHM$ is $E$ . Its kinetic energy at half the amplitude from mean position will be :

Discussion

33.	Energy stored in the form of electric field within spherical region of a uniformly charged sphere of charge Q is _______. (Charge is distributed within volume of sphere)
Answer» Energy stored in the form of electric field within spherical region of a uniformly charged sphere of charge $Q$ is _______. (Charge is distributed within volume of sphere)

Discussion

34.	A uniform rod of length L is suspended from one end such that it is free to rotate about an axis passing through that end and perpendicular to the length. What minimum speed must be imparted to the lower end so that the rod completes one full revolution?
Answer» A uniform rod of length L is suspended from one end such that it is free to rotate about an axis passing through that end and perpendicular to the length. What minimum speed must be imparted to the lower end so that the rod completes one full revolution?

Discussion

35.	From a spherical mirror, the graph of 1/v versus 1/u is given by
Answer» From a spherical mirror, the graph of 1/v versus 1/u is given by

Discussion

36.	Find the tension in the string connected to the block of mass 4 kg. Assume the strings and pulleys to be ideal. (Take g=10 m/s2)
Answer» Find the tension in the string connected to the block of mass $4 kg$ . Assume the strings and pulleys to be ideal. (Take $g = 10 m / s^{2})$

Discussion

37.	Co-efficient of linear expansion of brass and steel rods are α1 and α2 respectively. Lengths of brass and steel rods are L1 and L2 respectively. If (L2−L1) is maintained same at all the temperatures, which one of the following relations holds good?
Answer» Co-efficient of linear expansion of brass and steel rods are $α_{1}$ and $α_{2}$ respectively. Lengths of brass and steel rods are $L_{1}$ and $L_{2}$ respectively. If $(L_{2} - L_{1})$ is maintained same at all the temperatures, which one of the following relations holds good?

Discussion

38.	In the figure below, WAB and WCD are work done during process AB and CD. Which one of the following options is correct?
Answer» In the figure below, $W_{A B}$ and $W_{C D}$ are work done during process $A B$ and $C D$ . Which one of the following options is correct?

Discussion

39.	A body of mass 1 kg is subjected to a force of 20 N for 10 seconds after which the force ceases to act. What distance would it travel in the next 10 seconds.
Answer» A body of mass 1 kg is subjected to a force of 20 N for 10 seconds after which the force ceases to act. What distance would it travel in the next 10 seconds.

Discussion

40.	The system shown in the figure consists of three springs and two rods of the same material as shown in the figure. The springs are initially relaxed and there is no friction. The temperature of the rods is increased by ΔT. The coefficient of linear expansion of the material of the rods is α. Then, energy stored in the spring 1, when the system is in equilibrium, is:
Answer» The system shown in the figure consists of three springs and two rods of the same material as shown in the figure. The springs are initially relaxed and there is no friction. The temperature of the rods is increased by $Δ T$ . The coefficient of linear expansion of the material of the rods is $α$ . Then, energy stored in the spring $1$ , when the system is in equilibrium, is:

Discussion

41.	Find the value of x;v^x=pressure ^3/2×density ^3/2
Answer» Find the value of x;v^x=pressure ^3/2×density ^3/2

Discussion

42.	A ball moving with a velocity of 9 m/sec collides with another similar stationary ball. After the collision both the balls move in directions making an angle of 30° with the initial direction. After the collision, their speed will be:-
Answer» A ball moving with a velocity of 9 m/sec collides with another similar stationary ball. After the collision both the balls move in directions making an angle of 30° with the initial direction. After the collision, their speed will be:-

Discussion

43.	Actually electrostatic electric charges are static in condition but how will it experience a continuous charges???????
Answer» Actually electrostatic electric charges are static in condition but how will it experience a continuous charges???????

Discussion

44.	State whether an object can move with a constant acceleration but zero velocity. If possible, give an example.
Answer» State whether an object can move with a constant acceleration but zero velocity. If possible, give an example.

Discussion

45.	Newton's laws of motion.What is the term momentum really mean???
Answer» Newton's laws of motion.What is the term momentum really mean???

Discussion

46.	Oscillation performed by a body dropped in a tunnel passing through the centre of earth
Answer» Oscillation performed by a body dropped in a tunnel passing through the centre of earth

Discussion

47.	Differentiation of y=ex lnx is
Answer» Differentiation of $y = e^{x} ln x$ is

Discussion

48.	In an unbiased p-n junction, holes diffuse from the p-region to n-region because
Answer» In an unbiased p-n junction, holes diffuse from the p-region to n-region because

Discussion

49.	A boy throws a ball with a velocity u at an angle θ with the horizontal. At the same instant he starts running with uniform velocity to catch the ball before it hits the ground. To achieve this, he should run with a velocity of :
Answer» A boy throws a ball with a velocity u at an angle θ with the horizontal. At the same instant he starts running with uniform velocity to catch the ball before it hits the ground. To achieve this, he should run with a velocity of :

Discussion

50.	The height (in cm) risen by a liquid in a capillary tube having diameter of its bore as 1 mm is given by (Take S=0.075 N/m, density =1 gm/cc, contact angle = 0°)
Answer» The height (in $cm$ ) risen by a liquid in a capillary tube having diameter of its bore as $1 mm$ is given by (Take $S = 0.075 N/m$ , density $= 1 gm/cc$ , contact angle = 0°)

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A particle with mass m is held in circular orbit around the origin by an attractive force F(r)=-Dr; where D is a positive constant. Assume that the Bohr model idea that ,the angular momentum is quantized i.e. it takes only integral multiples of h2π holds. The value of nth orbital radius is

An electron enters the region between the plates of a parallel-plate capacitor with same initial velocity at an angle θ to the plants. The plate width is l and the plate separation is d. The electron follows the path shown, just missing the upper plate. Neglect gravity. Then,

How much work must be done to pull apart the electron and the proton that make up the Hydrogen atom, if the atom is initially in the state with n = 2

A source of sound S moving with constant speed approaches a junction A. If the original frequency produced by the source is 640 Hz then for the situation shown in the figure, the apparent frequency heard by the observer at rest at O will be [speed of sound =340 m/s]

[MP PET 1992]

Two different liquids are flowing in two tubes of equal radius. The ratio of coefficients of viscosity of liquids is 52:49 and the ratio of their densities is 13:1, then the ratio of their critical velocities will be

What happens to the motion of any body after a particular time, when the directions of its velocity and acceleration are opposite to each other?

A body falls freely from the top of a tower. It covers 36% of the total height in the last second before striking the ground level. The height of the tower is

A sample of radioactive material has a mass m, decay constant λ and molecular weight M. If NA is Avogadro's number, the initial activity of the sample is:

Block of mass 3 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in ms−2 at t = 0. (Take g=10ms−2

A ring of mass ‘m’ and radius ‘R’ rolls on a horizontal rough surface without slipping due to an applied force ‘F’. The friction force acting on the ring is

An ideal gas undergoes a process AB as shown in figure. Which of the following is true for the gas?

A stone weighing 1 kg is whirled in a vertical circle at the end of a rope of length 0.5 m. Stone completes the vertical circle with minimum possible speed. The velocity of the stone midway, when the string is horizontal is (Take g=10 m/s2)

The moon takes about 27.3 days to revolve round the earth in a nearly circular orbit of radius 3.84×105 km. Calculate the mass of the earth from these data.

Coil of 800 turns of effective area 0.05 m2 is kept perpendicular to a magnetic field of magnitude 5×10−5 T. When the plane of the coil is rotated by 90°around any of its coplanar axis in 0.1 s, the emf induced in the coil will be

A metallic sphere floats in an immiscible mixture of water and a liquid such that its 45th volume is in water and 15th volume is in the liquid. Then, density of the metal is

A long U tube is filled with a liquid of density ‘ρ ’ such that length of the tube above liquid is ‘a’ in both arm. One side of tube (right arm) is sealed and the tube is inverted (‘P0’ atmospheric pressure).

The angle of a prism is A and one of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the second (silvered) surface The refractive index of the material of the prism is

The figure shows two blocks of masses 6 kg and 4 kg placed on a frictionless surface and connected with spring. An external kick gives a velocity 15 m/s to 6 kg block and 10 m/s to 4 kg block in the opposite direction as shown. Find the velocity gain by the centre of mass of the system.

An object of specific gravity ρ is hung from a thin steel wire. The fundamental frequency (in Hz) is 300 Hz. The object is immersed in water with specific gravity ρw, so that one half its volume is submerged. The new fundamental frequency (in Hz) is

The force vs displacement graph of a moving body is as shown in the figure. What is the work done as the body moves from x=5 m to x=35 m?

​​​​ a ball thrown vertically upward with a velocity u it takes t0 seconds to reach the highest point the distance travelled in the last t seconds of its ascend( t &lt; t0 second)?

The potential energy for a force field →F is given by U(x,y)=cos(x+y). The force acting on a particle at the position given by coordinates (0,π4) is

A Carnot engine takes 3×10^6cal of heat from a Reservoir at 627°cand gives to async at 27 °c the work done by the engine is

When a ceiling fan is switched on it starts from rest, while completing the 10th revolution it has angular velocity of 40 rad/s , find the angular acceleration of the fan ? (Assume uniform angular acceleration)

What is meant by dimensionless quantity?

The total vibrational energy of a particle in SHM is E. Its kinetic energy at half the amplitude from mean position will be :

Energy stored in the form of electric field within spherical region of a uniformly charged sphere of charge Q is _______. (Charge is distributed within volume of sphere)

A uniform rod of length L is suspended from one end such that it is free to rotate about an axis passing through that end and perpendicular to the length. What minimum speed must be imparted to the lower end so that the rod completes one full revolution?

From a spherical mirror, the graph of 1/v versus 1/u is given by

Find the tension in the string connected to the block of mass 4 kg. Assume the strings and pulleys to be ideal. (Take g=10 m/s2)

Co-efficient of linear expansion of brass and steel rods are α1 and α2 respectively. Lengths of brass and steel rods are L1 and L2 respectively. If (L2−L1) is maintained same at all the temperatures, which one of the following relations holds good?

In the figure below, WAB and WCD are work done during process AB and CD. Which one of the following options is correct?

A body of mass 1 kg is subjected to a force of 20 N for 10 seconds after which the force ceases to act. What distance would it travel in the next 10 seconds.

Find the value of x;v^x=pressure ^3/2×density ^3/2

A ball moving with a velocity of 9 m/sec collides with another similar stationary ball. After the collision both the balls move in directions making an angle of 30° with the initial direction. After the collision, their speed will be:-

Actually electrostatic electric charges are static in condition but how will it experience a continuous charges???????

State whether an object can move with a constant acceleration but zero velocity. If possible, give an example.

Newton's laws of motion.What is the term momentum really mean???

Oscillation performed by a body dropped in a tunnel passing through the centre of earth

Differentiation of y=ex lnx is

In an unbiased p-n junction, holes diffuse from the p-region to n-region because

A boy throws a ball with a velocity u at an angle θ with the horizontal. At the same instant he starts running with uniform velocity to catch the ball before it hits the ground. To achieve this, he should run with a velocity of :

The height (in cm) risen by a liquid in a capillary tube having diameter of its bore as 1 mm is given by (Take S=0.075 N/m, density =1 gm/cc, contact angle = 0°)

a ball thrown vertically upward with a velocity u it takes t0 seconds to reach the highest point the distance travelled in the last t seconds of its ascend( t < t0 second)?