Archives

A student is performing an experiment using a resonance column and a tuning fork of frequency 244

A student is performing an experiment using a resonance column and a tuning fork of frequency 244 s-1. The student is told that the air in the... View Article

The system shown below is in equilibrium find the acceleration of block m1, immediately after spring k2 is cut

The system shown below is in equilibrium. What is the acceleration of block m1, immediately after spring k2 is cut? (a) 0 (b) (c) g (d)... View Article

The rectangular loop shown in the figure is co-planar with the straight infinitely long wire carrying current i_0. The magnetic flux through the loop is

The rectangular loop shown in the figure is co-planar with the straight infinitely long wire carrying current 5 A. The magnetic flux through the... View Article

If work done in increasing the size of rectangular soap is

If work done in increasing the size of rectangular soap film with dimensions 8 cm × 3.75 cm to 10 cm × 6 cm is 2 × 10–4 J. The surface tension of... View Article

Four cubes of side “a” each of mass 40gm, 20gm,10gm and 20gm are arranged in xy plane as shown in figure. The coordinates of centre of mass of the combination with respect to o, are

Four cubes of side “a” each of mass 40gm, 20gm,10gm and 20gm are arranged in xy plane as shown in figure. The coordinates of centre of mass... View Article

A plane em wave travels in free space along x direction.

A plane em wave travels in free space along x direction. If the value of in V/m at the point is (a) (b) (c) (d) Answer: (d)... View Article

At what distance on the axis, from the centre of a circular current carrying coil of radius r, the magnetic field becomes 1/8th of the magnetic field at centre?

The magnetic field becomes 1/8th of the magnetic field at (a) (b) (c) (d) Answer: (c)... View Article

A balloonist releases a bag from a balloon, rising at 40 ms^–1 at a time when the balloon is 100 m above the ground. If g = 10 ms^–2, then the bag reaches the ground in

The bag reaches the ground in (a) 18 s (b) 16 s (c) 10 s (d) 20 s Answer: (c) 10 s... View Article

Suppose the parallel metal plates shown in figure at 0.50 cm apart and are connected to 90 V battery. What is the surface charge density of plates?

Surface density of the plate is equal to (a) (b) (c) (d) Answer: (d)... View Article

A storage battery has an emf of 25 V and internal resistance is 0.20 ω. What is its terminal voltage when it is being charged by a current of 8 A?

Its terminal voltage is (a) 23.4 V (b) 33.4 V (c) 66.4 V (d) 78.5 V Answer: (a) 23.4 V... View Article

An object is projected along the normal to an inclined surface of inclination θ with speed v. The time in which it lands back on the incline is

The time in which it lands back on the incline is (a) (b) (c) (d) Answer: (b)... View Article

A copper wire of a diameter of 1.02 mm carries a current of 1.7 amp. The drift velocity (vd) of electrons in the wire is (The number density of electrons in copper = 8.5×10^28 m^3.)

The drift velocity (vd) of electrons in the wire is (a) 1.25 mm/sec (b) 1.75 mm/sec (c) 1.5 mm/sec (d) 2.5 mm/sec Answer: (c) 1.5 mm/sec... View Article

An object undergoes an acceleration of 8ms^-2 starting from rest. Find the distance travelled in 4 seconds.

Solution: We can find the distance, by using the following formula: Substituting the values in the equation, we get... View Article

Solid A is a very hard electrical insulator in solid as well as in molten state and melts at an extremely high temp. What type of solid is it?

The given properties are examples of covalent solids. Examples of covalent solids are diamond and quartz.... View Article

The activity of a radioactive substance is 4700 per minute.

The activity of a radioactive substance is 4700 per minute. Five minutes later the activity is 2700 per minute. The decay constant is (a) 0.1108... View Article

How far away from the surface of the earth, does the acceleration due to gravity will be reduced by 36% of its value on the surface of the earth if the radius of the earth is 6400 km?

At what height from the surface of the earth, does the acceleration due to gravity will be reduced by 36% of its value on the surface of the... View Article

A force F = 3i 4j Newton acts on a particle which move from a position (2m , 3 m) to ( 3m, 0m). Then the work done is:

A force F = 3i + 4j Newton acts on a particle that moves from a position (2m, 3 m) to ( 3m, 0m). Then the work done is: (a) −9j (b)... View Article

A body cools from 67c to 37c. If this takes time t when the surrounding temperature is 27c, what will be the time taken if the surrounding temperature is 7c?

A body cools from 67c to 37c. If this takes time t when the surrounding temperature is 27c, what will be the time taken if the surrounding... View Article

Uniform magnetic field b_0 exists in circular region, a charge particle (q, m) is projected from (a, 0) with velocity maximum value of v_0 so that particle does not exit the magnetic field region.

Uniform magnetic field b_0 exists in the circular region, a charged particle (q, m) is projected from (a, 0) with a velocity maximum value of v_0... View Article

A particle of mass 2 kg is performing SHM, given by equation x=10sin2πt (x is in m and t in s). The work done on the particle in time 0.25 s to 0.75 s, will be

A particle of mass 2 kg is performing SHM, given by equation x=10sin2πt (x is in m and t in s). The work done on the particle in time 0.25 s to... View Article