50278 + Interview Questions in Physics

1.	A disc of radius 0.1 m rolls without sliding on a horizontal surface with a velocity of 6 m/s. It then ascends a smooth continuous track as shown in figure. The height upto which it will ascend is (g=10 m/ s2)
Answer» A disc of radius 0.1 m rolls without sliding on a horizontal surface with a velocity of 6 m/s. It then ascends a smooth continuous track as shown in figure. The height upto which it will ascend is (g=10 m/ $s^{2}$ )

1.

A disc of radius 0.1 m rolls without sliding on a horizontal surface with a velocity of 6 m/s. It then ascends a smooth continuous track as shown in figure. The height upto which it will ascend is (g=10 m/ s2)

Answer»

A disc of radius 0.1 m rolls without sliding on a horizontal surface with a velocity of 6 m/s. It then ascends a smooth continuous track as shown in figure. The height upto which it will ascend is (g=10 m/ $s^{2}$ )

Discussion

2.	A small bob hangs at one end of a massless string of length l and the other end of the string is fixed. The bob is given a sharp hit to impart it a horizontal speed of √3gl. Find the angle (θ) made by the string with the vertical when the string becomes slack.
Answer» A small bob hangs at one end of a massless string of length $l$ and the other end of the string is fixed. The bob is given a sharp hit to impart it a horizontal speed of $\sqrt{3 g l}$ . Find the angle $(θ)$ made by the string with the vertical when the string becomes slack.

Discussion

3.	Two particles of equal mass go round a circle of radius R under the action of their mutual gravitational attraction. The speed of each particle is--
Answer» Two particles of equal mass go round a circle of radius R under the action of their mutual gravitational attraction. The speed of each particle is--

Discussion

4.	What is difference between Velocity and Speed?
Answer» What is difference between Velocity and Speed?

Discussion

5.	In a large room, a person receives direct sound waves from a source 120 metres away from him. He also receives waves from the same source which reach him, being reflected from the 25 metre high ceiling at a point halfway between them. The two waves interfere constructively for wavelength of
Answer» In a large room, a person receives direct sound waves from a source 120 metres away from him. He also receives waves from the same source which reach him, being reflected from the 25 metre high ceiling at a point halfway between them. The two waves interfere constructively for wavelength of

Discussion

6.	Minimum horizontal force F required to keep the smaller block stationary with respect to the bigger block.
Answer» Minimum horizontal force $F$ required to keep the smaller block stationary with respect to the bigger block.

Discussion

7.	What is the difference between polarizability and polarisation?
Answer» What is the difference between polarizability and polarisation?

Discussion

8.	A man is standing between two parallel cliffs and fires a gun. If he hears first and second echoes after 1.5 s and 3.5 s respectively, the distance between the cliffs is (Velocity of sound in air = 340 ms−1)
Answer» A man is standing between two parallel cliffs and fires a gun. If he hears first and second echoes after $1.5 s$ and $3.5 s$ respectively, the distance between the cliffs is (Velocity of sound in air = $340 m s^{- 1}$ )

Discussion

9.	The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then
Answer» The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

9.

The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

Answer»

The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

Discussion

10.	Where is collision happening in this question? How to solve it?A cart of mass 50 kg is moving on a straight track with a speed of 12 metre per second a mass of 10 kg is gently put into the card what will be the velocity of the cart after this
Answer» Where is collision happening in this question? How to solve it?A cart of mass 50 kg is moving on a straight track with a speed of 12 metre per second a mass of 10 kg is gently put into the card what will be the velocity of the cart after this

Discussion

11.	A tuning fork of frequency 480 Hz is used to vibrate a sonometer wire having natural frequency 410 Hz. The wire will vibrate with a frequency,
Answer» A tuning fork of frequency 480 Hz is used to vibrate a sonometer wire having natural frequency 410 Hz. The wire will vibrate with a frequency,

Discussion

12.	The moment of inertia of a thin square plate ABCD, of uniform thickness about an axis passing through the centre O and perpendicular to the plane of the plate is
Answer» The moment of inertia of a thin square plate ABCD, of uniform thickness about an axis passing through the centre O and perpendicular to the plane of the plate is

12.

The moment of inertia of a thin square plate ABCD, of uniform thickness about an axis passing through the centre O and perpendicular to the plane of the plate is

Answer»

The moment of inertia of a thin square plate ABCD, of uniform thickness about an axis passing through the centre O and perpendicular to the plane of the plate is

Discussion

13.	The dimensional formula for impulse is
Answer» The dimensional formula for impulse is

Discussion

14.	In a series resonant circuit the ac voltages across R, inductance L and capacitance C are 5V, 10 V and 10V respectively. The ac voltage applied to the circuit will be:
Answer» In a series resonant circuit the ac voltages across R, inductance L and capacitance C are 5V, 10 V and 10V respectively. The ac voltage applied to the circuit will be:

Discussion

15.	the initial velocity of particle is u (a=0) and the accelaration is given by bt3/2. which of the following relationship is valide???? 1) v= u+bt3/2 2) v= u+3bt3/2 3) v= u+2/5bt5/2 4) v= u+bt5/2 the answer is 3th option..... how????????
Answer» the initial velocity of particle is u (a=0) and the accelaration is given by bt^3/2. which of the following relationship is valide???? 1) v= u+bt^3/2 2) v= u+3bt³/2 3) v= u+2/5bt^5/2 4) v= u+bt^5/2 the answer is 3th option..... how????????

Discussion

16.	The energy of a photon is equal to the kinetic energy of a proton. The energy of the photon is E. Let λ1 be the de-Broglie wavelength of the proton and λ2 be the wavelength of the photon. The ratio λ1/λ2 is proportional to
Answer» The energy of a photon is equal to the kinetic energy of a proton. The energy of the photon is E. Let $λ_{1}$ be the de-Broglie wavelength of the proton and $λ_{2}$ be the wavelength of the photon. The ratio $λ_{1} / λ_{2}$ is proportional to

Discussion

17.	The ratio of angular dispersion of to the angle of deviation for the mean wavelength is called Dispersive Power. Represented by
Answer» The ratio of angular dispersion of to the angle of deviation for the mean wavelength is called Dispersive Power. Represented by

Discussion

18.	The phenomenon in which polar crystals on heating produce electricity is called
Answer» The phenomenon in which polar crystals on heating produce electricity is called

Discussion

19.	If vectors P, Q and R have magnitude 5, 12 and 13 units and →P+→Q=→R, the angle between Q and R is
Answer» If vectors P, Q and R have magnitude 5, 12 and 13 units and $\to P + \to Q = \to R$ , the angle between Q and R is

Discussion

20.	The work done in the process that follows V2.T3 = constant in going from T0 to 2T0 is
Answer» The work done in the process that follows $V^{2} . T^{3}$ = constant in going from $T_{0}$ to $2 T_{0}$ is

Discussion

21.	Two trains each having a speed of 30 kmph are headed at each other on the same straight track. A bird that can fly at 60 kmph flies off from one train when they are 60 km apart and heads directly for the other train. On reaching the other train, it flies directly back to the first and so forth. How many trips can the bird make from one train to the other before the crash. Also find the total distance that the bird travels.
Answer» Two trains each having a speed of $30 kmph$ are headed at each other on the same straight track. A bird that can fly at $60 kmph$ flies off from one train when they are $60 km$ apart and heads directly for the other train. On reaching the other train, it flies directly back to the first and so forth. How many trips can the bird make from one train to the other before the crash. Also find the total distance that the bird travels.

Discussion

22.	Two trains each having a speed of 30 km/h are headed at each other on the same straight track. A bird that can fly at 60 km/h flies off from one train when they are 60 km apart and heads directly for the other train. On reaching the other train, it flies directly back to the first and so forth. How many trips (n) can the bird make from one train to the other before the trains crash. Find the total distance that the bird travels assuming bird to be a point object.
Answer» Two trains each having a speed of $30 km/h$ are headed at each other on the same straight track. A bird that can fly at $60 km/h$ flies off from one train when they are $60 km$ apart and heads directly for the other train. On reaching the other train, it flies directly back to the first and so forth. How many trips $(n)$ can the bird make from one train to the other before the trains crash. Find the total distance that the bird travels assuming bird to be a point object.

Discussion

23.	Define Radius of gyration.
Answer» Define Radius of gyration.

Discussion

24.	The quantity pVkT represents
Answer» The quantity $\frac{p V}{k T}$ represents

Discussion

25.	A photon of 300 nm is absorbed by a gas and then reemitted two photons. One of the reemitted photon has wavelenght 496 nm, then the other photon has
Answer» A photon of $300 n m$ is absorbed by a gas and then reemitted two photons. One of the reemitted photon has wavelenght $496 n m$ , then the other photon has

Discussion

26.	A car travels from A to B at a speed of 20 km/h and returns at a speed of 30 km/h. The average speed of the car for the whole journey is
Answer» A car travels from $A$ to $B$ at a speed of $20 km/h$ and returns at a speed of $30 km/h$ . The average speed of the car for the whole journey is

Discussion

27.	When two soap bubbles of radius and r1 and r2 (r2>r1)coalesce, the radius of curvature of common surface is
Answer» When two soap bubbles of radius and $r_{1}$ and $r_{2} (r_{2} > r_{1})$ coalesce, the radius of curvature of common surface is

Discussion

28.	For a body to be able to loop a vertical circle of radius R, the minimum velocity required at its lowest point is:
Answer» For a body to be able to loop a vertical circle of radius R, the minimum velocity required at its lowest point is:

Discussion

29.	The weight of one atom of uranium is 238 amu its actual weight in gm is?
Answer» The weight of one atom of uranium is 238 amu its actual weight in gm is?

Discussion

30.	A ball of mass 9x10-5kg carries a charge is 5x10-6 C . What must be the magnitude and sign of the charge on another ball held directly 2cm above the first ball so that the first ball remains stationary .
Answer» A ball of mass 9x10^-5kg carries a charge is 5x10^-6C . What must be the magnitude and sign of the charge on another ball held directly 2cm above the first ball so that the first ball remains stationary .

Discussion

31.	Two loudspeakers L1 and L2 driven by a common oscillator and amplifier, are arranged as shown. The frequency of the oscillator is gradually increased from zero and the detector at D records a series of maxima and minima. If the speed of sound is 330 ms−1, then the frequency at which the first maximum is observed is
Answer» Two loudspeakers $L_{1}$ and $L_{2}$ driven by a common oscillator and amplifier, are arranged as shown. The frequency of the oscillator is gradually increased from zero and the detector at D records a series of maxima and minima. If the speed of sound is $330 m s^{- 1}$ , then the frequency at which the first maximum is observed is

31.

Two loudspeakers L1 and L2 driven by a common oscillator and amplifier, are arranged as shown. The frequency of the oscillator is gradually increased from zero and the detector at D records a series of maxima and minima. If the speed of sound is 330 ms−1, then the frequency at which the first maximum is observed is

Answer»

Two loudspeakers $L_{1}$ and $L_{2}$ driven by a common oscillator and amplifier, are arranged as shown. The frequency of the oscillator is gradually increased from zero and the detector at D records a series of maxima and minima. If the speed of sound is $330 m s^{- 1}$ , then the frequency at which the first maximum is observed is

Discussion

32.	An a.c. voltage source E = 200 √2 sin 100t is connected across a circuit containing an a.c.ammeter and a capacitor of capacitance 1μF. The reading of the ammeter is:
Answer» An a.c. voltage source E = 200 √2 sin 100t is connected across a circuit containing an a.c.ammeter and a capacitor of capacitance 1μF. The reading of the ammeter is:

Discussion

33.	The Vaporisation process is always
Answer» The Vaporisation process is always

Discussion

34.	From above graph choose correct option for t1 to t2 where t1 is the time at which velocity of particle = 0 t2 is the time at which velocity of particle is negative.
Answer» From above graph choose correct option for $t_{1}$ to $t_{2}$ where $t_{1}$ is the time at which velocity of particle = 0 $t_{2}$ is the time at which velocity of particle is negative.

34.

From above graph choose correct option for t1 to t2 where t1 is the time at which velocity of particle = 0 t2 is the time at which velocity of particle is negative.

Answer»

From above graph choose correct option for $t_{1}$ to $t_{2}$ where $t_{1}$ is the time at which velocity of particle = 0 $t_{2}$ is the time at which velocity of particle is negative.

Discussion

35.	How to convert 13.6electron volts to joules?
Answer» How to convert 13.6electron volts to joules?

Discussion

36.	A simple pendulum with length L and mass M of the bob is vibrating with amplitude a. Then the maximum tension in the string is,
Answer» A simple pendulum with length L and mass M of the bob is vibrating with amplitude a. Then the maximum tension in the string is,

Discussion

37.	The root mean square (R.M.S.) Speed V of the molecules of an ideal gas is given by the expressions, v = √ (3RT/M) and v = √ (3KT/m) where R is universal gas constant, T is the absolute (Kelvin) temperature M is the molar mass, K is Boltzman's constant and M is the molecular mass. The R.M.S. speed of oxygen molecules (O2) at temperature T1 is V1. When the temperature is doubled, if the oxygen molecules are dissociated into atomic oxygen, what will be R.M.S. speed of oxygen atoms? (Treat the gas as ideal).
Answer» The root mean square (R.M.S.) Speed V of the molecules of an ideal gas is given by the expressions, v = √ (3RT/M) and v = √ (3KT/m) where R is universal gas constant, T is the absolute (Kelvin) temperature M is the molar mass, K is Boltzman's constant and M is the molecular mass. The R.M.S. speed of oxygen molecules (O₂) at temperature T₁ is V₁. When the temperature is doubled, if the oxygen molecules are dissociated into atomic oxygen, what will be R.M.S. speed of oxygen atoms? (Treat the gas as ideal).

37.

The root mean square (R.M.S.) Speed V of the molecules of an ideal gas is given by the expressions, v = √ (3RT/M) and v = √ (3KT/m) where R is universal gas constant, T is the absolute (Kelvin) temperature M is the molar mass, K is Boltzman's constant and M is the molecular mass. The R.M.S. speed of oxygen molecules (O2) at temperature T1 is V1. When the temperature is doubled, if the oxygen molecules are dissociated into atomic oxygen, what will be R.M.S. speed of oxygen atoms? (Treat the gas as ideal).

Answer»

The root mean square (R.M.S.) Speed V of the molecules of an ideal gas is given by the expressions,

v = √ (3RT/M) and

v = √ (3KT/m) where R is universal gas constant, T is the absolute (Kelvin) temperature M is the molar mass, K is Boltzman's constant and M is the molecular mass. The R.M.S. speed of oxygen molecules (O₂) at temperature T₁ is V₁. When the temperature is doubled, if the oxygen molecules are dissociated into atomic oxygen, what will be R.M.S. speed of oxygen atoms? (Treat the gas as ideal).

Discussion

38.	A person feels 2.5% difference of frequency of a motor-car horn. If the motor-car is moving to the person and the velocity of sound is 320 m/sec, then the velocity of car will be
Answer» A person feels 2.5% difference of frequency of a motor-car horn. If the motor-car is moving to the person and the velocity of sound is 320 m/sec, then the velocity of car will be

Discussion

39.	The ends of a stretched wire of length L are fixed at x=0 and x=L In one experiment, the displacement of the wire is y1=Asin (πxL)sin ωt and energy is E1, and in another experiment its displacement is y2=Asin(2πxL)sin 2ωt and energy is E2. Then
Answer» The ends of a stretched wire of length L are fixed at x=0 and x=L In one experiment, the displacement of the wire is $y_{1} = A s i n (\frac{π x}{L}) s i n ω t$ and energy is $E_{1}$ , and in another experiment its displacement is $y_{2} = A s i n (\frac{2 π x}{L}) s i n 2 ω t$ and energy is $E_{2}$ . Then

39.

The ends of a stretched wire of length L are fixed at x=0 and x=L In one experiment, the displacement of the wire is y1=Asin (πxL)sin ωt and energy is E1, and in another experiment its displacement is y2=Asin(2πxL)sin 2ωt and energy is E2. Then

Answer»

The ends of a stretched wire of length L are fixed at x=0 and x=L In one experiment, the displacement of the wire is $y_{1} = A s i n (\frac{π x}{L}) s i n ω t$ and energy is $E_{1}$ , and in another experiment its displacement is $y_{2} = A s i n (\frac{2 π x}{L}) s i n 2 ω t$ and energy is $E_{2}$ . Then

Discussion

40.	A S.H.M. has amplitude 'a' and time period T. The maximum velocity will be [MP PMT 1985; CPMT 1997; UPSEAT 1999]
Answer» A S.H.M. has amplitude 'a' and time period T. The maximum velocity will be [MP PMT 1985; CPMT 1997; UPSEAT 1999]

40.

A S.H.M. has amplitude 'a' and time period T. The maximum velocity will be [MP PMT 1985; CPMT 1997; UPSEAT 1999]

Answer»

A S.H.M. has amplitude 'a' and time period T. The maximum velocity will be

[MP PMT 1985; CPMT 1997; UPSEAT 1999]

Discussion

41.	Why does a cyclist bend or lean during a turn?
Answer» Why does a cyclist bend or lean during a turn?

Discussion

42.	The variation in velocity of a particle moving along a straight line is shown in the figure. If the particle is moving along x-axis with initial position x=10 m, find the final position of particle.
Answer» The variation in velocity of a particle moving along a straight line is shown in the figure. If the particle is moving along x-axis with initial position $x = 10 m$ , find the final position of particle.

Discussion

43.	A gas is compressed at a constant pressure of 50N/m2 from a volume of 10m3 to a volume of 4m3.Energy of 100J then added to the gas by heating.Its internal energy is
Answer» A gas is compressed at a constant pressure of $50 N / m^{2}$ from a volume of $10 m^{3}$ to a volume of $4 m^{3}$ .Energy of 100J then added to the gas by heating.Its internal energy is

Discussion

44.	On an X temperature scale, water freezes at −125.0∘X and boils at 375.0∘X. On a Y temperature scale, water freezes at −70.0∘Y and boils at −30.0∘Y. The value of temperature on X scale equal to the temperature of 50.0∘Y on Y scale is:
Answer» On an X temperature scale, water freezes at $- {125.0}^{\circ}$ X and boils at ${375.0}^{\circ}$ X. On a Y temperature scale, water freezes at $- {70.0}^{\circ}$ Y and boils at $- {30.0}^{\circ}$ Y. The value of temperature on X scale equal to the temperature of ${50.0}^{\circ}$ Y on Y scale is:

Discussion

45.	A water surfer is moving at a speed of 15 m/s. When he is surfing in the direction of wave, he swingsupwards every 0.8 s because of wave crests. While surfing in opposite direction to that of wave motion, he swings upwards every 0.6 s. Determine the wavelength of transverse component of the water wave.
Answer» A water surfer is moving at a speed of 15 m/s. When he is surfing in the direction of wave, he swingsupwards every 0.8 s because of wave crests. While surfing in opposite direction to that of wave motion, he swings upwards every 0.6 s. Determine the wavelength of transverse component of the water wave.

Discussion

46.	The pressure of the gas in a constant volume gas thermometer at steam point (373.15K) is 1.5×104 Pa. What will be the pressure at the triple point of water ?
Answer» The pressure of the gas in a constant volume gas thermometer at steam point (373.15K) is $1.5 \times 10^{4} P a$ . What will be the pressure at the triple point of water ?

Discussion

47.	An electron having a kinetic energy of 100 eV circulates in a path of radius 10 cm in a magnetic field. Find the magnetic field and the number of revolutions per second made by the electron.
Answer» An electron having a kinetic energy of 100 eV circulates in a path of radius 10 cm in a magnetic field. Find the magnetic field and the number of revolutions per second made by the electron.

Discussion

48.	The motion of a body is given by dvdt=6−3v where v is the velocity (in ms−1) at a time t (in seconds). The body is at rest at t = 0. The terminal speed of the body is
Answer» The motion of a body is given by $\frac{d v}{d t} = 6 - 3 v$ where $v$ is the velocity (in $m s^{- 1}$ ) at a time $t$ (in seconds). The body is at rest at t = 0. The terminal speed of the body is

Discussion

49.	Sodium and copper have work functions 2.3eV and 4.5eV respectively. Then the ratio of their threshold wavelengths is nearest to
Answer» Sodium and copper have work functions 2.3eV and 4.5eV respectively. Then the ratio of their threshold wavelengths is nearest to

Discussion

50.	A car of mass 'm' is driven with acceleration 'a' along a straight level road against a constant external resistive force 'R'. When the velocity of the car is 'V', the rate at which the engine of the car is doing work will be
Answer» A car of mass 'm' is driven with acceleration 'a' along a straight level road against a constant external resistive force 'R'. When the velocity of the car is 'V', the rate at which the engine of the car is doing work will be

50.

A car of mass 'm' is driven with acceleration 'a' along a straight level road against a constant external resistive force 'R'. When the velocity of the car is 'V', the rate at which the engine of the car is doing work will be

Answer»

A car of mass 'm' is driven with acceleration 'a' along a straight level road against a constant external resistive force 'R'. When the velocity of the car is 'V', the rate at which the engine of the car is doing work will be

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A disc of radius 0.1 m rolls without sliding on a horizontal surface with a velocity of 6 m/s. It then ascends a smooth continuous track as shown in figure. The height upto which it will ascend is (g=10 m/ s2)

A small bob hangs at one end of a massless string of length l and the other end of the string is fixed. The bob is given a sharp hit to impart it a horizontal speed of √3gl. Find the angle (θ) made by the string with the vertical when the string becomes slack.

Two particles of equal mass go round a circle of radius R under the action of their mutual gravitational attraction. The speed of each particle is--

What is difference between Velocity and Speed?

In a large room, a person receives direct sound waves from a source 120 metres away from him. He also receives waves from the same source which reach him, being reflected from the 25 metre high ceiling at a point halfway between them. The two waves interfere constructively for wavelength of

Minimum horizontal force F required to keep the smaller block stationary with respect to the bigger block.

What is the difference between polarizability and polarisation?

A man is standing between two parallel cliffs and fires a gun. If he hears first and second echoes after 1.5 s and 3.5 s respectively, the distance between the cliffs is (Velocity of sound in air = 340 ms−1)

The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

Where is collision happening in this question? How to solve it?A cart of mass 50 kg is moving on a straight track with a speed of 12 metre per second a mass of 10 kg is gently put into the card what will be the velocity of the cart after this

A tuning fork of frequency 480 Hz is used to vibrate a sonometer wire having natural frequency 410 Hz. The wire will vibrate with a frequency,

The moment of inertia of a thin square plate ABCD, of uniform thickness about an axis passing through the centre O and perpendicular to the plane of the plate is

The dimensional formula for impulse is

In a series resonant circuit the ac voltages across R, inductance L and capacitance C are 5V, 10 V and 10V respectively. The ac voltage applied to the circuit will be:

the initial velocity of particle is u (a=0) and the accelaration is given by bt3/2. which of the following relationship is valide???? 1) v= u+bt3/2 2) v= u+3bt3/2 3) v= u+2/5bt5/2 4) v= u+bt5/2 the answer is 3th option..... how????????

The energy of a photon is equal to the kinetic energy of a proton. The energy of the photon is E. Let λ1 be the de-Broglie wavelength of the proton and λ2 be the wavelength of the photon. The ratio λ1/λ2 is proportional to

The ratio of angular dispersion of to the angle of deviation for the mean wavelength is called Dispersive Power. Represented by

The phenomenon in which polar crystals on heating produce electricity is called

If vectors P, Q and R have magnitude 5, 12 and 13 units and →P+→Q=→R, the angle between Q and R is

The work done in the process that follows V2.T3 = constant in going from T0 to 2T0 is

Define Radius of gyration.

The quantity pVkT represents

A photon of 300 nm is absorbed by a gas and then reemitted two photons. One of the reemitted photon has wavelenght 496 nm, then the other photon has

A car travels from A to B at a speed of 20 km/h and returns at a speed of 30 km/h. The average speed of the car for the whole journey is

When two soap bubbles of radius and r1 and r2 (r2&gt;r1)coalesce, the radius of curvature of common surface is

For a body to be able to loop a vertical circle of radius R, the minimum velocity required at its lowest point is:

The weight of one atom of uranium is 238 amu its actual weight in gm is?

A ball of mass 9x10-5kg carries a charge is 5x10-6 C . What must be the magnitude and sign of the charge on another ball held directly 2cm above the first ball so that the first ball remains stationary .

An a.c. voltage source E = 200 √2 sin 100t is connected across a circuit containing an a.c.ammeter and a capacitor of capacitance 1μF. The reading of the ammeter is:

The Vaporisation process is always

From above graph choose correct option for t1 to t2 where t1 is the time at which velocity of particle = 0 t2 is the time at which velocity of particle is negative.

How to convert 13.6electron volts to joules?

A simple pendulum with length L and mass M of the bob is vibrating with amplitude a. Then the maximum tension in the string is,

A person feels 2.5% difference of frequency of a motor-car horn. If the motor-car is moving to the person and the velocity of sound is 320 m/sec, then the velocity of car will be

The ends of a stretched wire of length L are fixed at x=0 and x=L In one experiment, the displacement of the wire is y1=Asin (πxL)sin ωt and energy is E1, and in another experiment its displacement is y2=Asin(2πxL)sin 2ωt and energy is E2. Then

A S.H.M. has amplitude 'a' and time period T. The maximum velocity will be [MP PMT 1985; CPMT 1997; UPSEAT 1999]

Why does a cyclist bend or lean during a turn?

The variation in velocity of a particle moving along a straight line is shown in the figure. If the particle is moving along x-axis with initial position x=10 m, find the final position of particle.

A gas is compressed at a constant pressure of 50N/m2 from a volume of 10m3 to a volume of 4m3.Energy of 100J then added to the gas by heating.Its internal energy is

On an X temperature scale, water freezes at −125.0∘X and boils at 375.0∘X. On a Y temperature scale, water freezes at −70.0∘Y and boils at −30.0∘Y. The value of temperature on X scale equal to the temperature of 50.0∘Y on Y scale is:

The pressure of the gas in a constant volume gas thermometer at steam point (373.15K) is 1.5×104 Pa. What will be the pressure at the triple point of water ?

An electron having a kinetic energy of 100 eV circulates in a path of radius 10 cm in a magnetic field. Find the magnetic field and the number of revolutions per second made by the electron.

The motion of a body is given by dvdt=6−3v where v is the velocity (in ms−1) at a time t (in seconds). The body is at rest at t = 0. The terminal speed of the body is

Sodium and copper have work functions 2.3eV and 4.5eV respectively. Then the ratio of their threshold wavelengths is nearest to

A car of mass 'm' is driven with acceleration 'a' along a straight level road against a constant external resistive force 'R'. When the velocity of the car is 'V', the rate at which the engine of the car is doing work will be

When two soap bubbles of radius and r1 and r2 (r2>r1)coalesce, the radius of curvature of common surface is