Physics Test - ...

A 2 kg block slides on a horizontal floor with a speed of 4 m/s. It strikes an uncompressed spring and compresses it till the block is motionless. The kinetic friction force is 15 N and spring constant is 10,000 N/m. The spring compresses by

Directions: In the following question, Statement - 1 (Assertion) is followed by Statement - 2 (Reason). The question has four options, out of which only one is correct.

Statement – 1: A coil is connected in series with a bulb and this combination is connected to an a.c. source. If an iron core is inserted in the coil, the brightness of the bulb will be reduced.

Statement – 2: When an iron core is inserted in the coil, its inductance decreases.

Using mass (M), length (L), time (T) and current (A) as fundamental quantities, the dimensions of permeability are

In a sample of radioactive material, what fraction of the initial number of active nuclei will remain undisintegrated after half of a half-life of the sample ?

A cylindrical vessel of radius r is filled with a liquid to a height h such that the force exerted by the liquid on the sides of the vessel is equal to that exerted at the bottom. The ratio h/r is

Constant forces \(\overrightarrow{{P}}=2 \hat{i}-5 \hat{\jmath}+6 \hat{k}\) and \(\overrightarrow{{Q}}=-\hat{i}+2 \hat{\jmath}-\hat{k}\) act on a particle. The work done when the particle is displaced from \(A\) whose position vector is \(4 \hat{\imath}-3 \hat{\jmath}-2 \hat{k}\), to \(B\) whose position vector is \(6 \hat{\imath}+\hat{\jmath}-3 \hat{k}\), is:

One face of a glass prism is silver polished. A light ray falls at an angle of 45° on the other face. After refraction, it is subsequently reflected from the silvered face and then, it retraces its path. The refracting angle of the prism is 30°. The refractive index of the material of the prism is

Two blocks of masses m₁ = 3 m and m₂ = 2 m are suspended from a rigid support by inextensible uniform wires A and B. Wire A has negligible mass and wire B has a mass m₃ = m as shown in the figure. The whole system of blocks, wires and the support has an upward acceleration a.

The tension at the mid-point C of wire B is

Which of the following is non-conservative force?

A small trolley of mass 2 kg resting on a horizontal frictionless turntable is connected by a light spring to the centre of the table. The relaxed length of the spring is 35 cm. When the turntable is rotated at an angular frequency of 10 rad s–1, the length of the spring becomes 40 cm. What is the force constant of the spring?