WBJEE Physics Test - 11 - JEE MCQ

A particle of mass 0.3 kg is subjected to a force F = -kx with k = 15 N-m^-1. What will be its initial acceleration, if it is released from a point 20 cm away from the origin?

The number of turns in the primary coil of a transformer is 200 and the number of turns in secondary coil is 10. If 240 V a.c. is applied to the primary, the output from secondary will be

On stretching a wire, the elastic energy stored per unit volume is

Charges   are placed at the four corners of a square of side 1m. The potential at the centre of the square is

A parallel plate capacitor of capacity C₀ is charged to a potential V 0 .
A) The energy stored in the capacitor when the battery is disconnected and the plate separation is doubled is E₁.
B) The energy stored in the capacitor when the charging battery is kept connected and the separation between the capacitor plates is doubled is E₂. Then value is

The escape velocity of an object from the earth depends upon the mass of the earth (M), its mean density (ρ),its radius (R) and gravitational constant (G). Thus the formula for escape velocity is

The magnetic field near a current carrying conductor is given by

A current carrying straight wire is kept along the axis of a circular loop carrying a current. The straight wire

A magnetic needle suspended by a silk thread is vibrating in the earth's magnetic field. If the temperature of the needle is increased by 700�C, then

If the radius of a soap bubble is four times that of another, then the ratio of their pressures will be

The average velocity of a body moving with uniform acceleration travelling a distance of 3.06 m is 0.34 ms⁻¹. If the change in velocity of the body is 0.18 ms⁻¹ during this time, its uniform acceleration is

The vector quantity among the following is

A bullet is fired from a canon with velocity 500 m/s. If the angle of projection is 15º and g = 10 m/s². Then the range is

Nuclear fusion occur in

In a simple harmonic motion displacement is half of its amplitude, what will be the ratio of K.E. and P.E.

Two simple harmonic motions act on a particle. These harmonic motions are x=A cos (ωt+δ);y =A cos (ωt+α) when δ=α+π/2, the resulting motion is

The spectrum obtained from a sodium vapour lamp is an example for

A particle of mass m is rotating in a plane in circular path of radius r. Its angular momentum is L. The centripetal force acting on the particle is

The angular velocity of second's hand of a watch is

In semi-conductor with the increase in temperature its resistance

In a P-N junction diode

540 g of ice at 0ºC is mixed with 540 g of water at 80ºC. The final temp. of the mixture in ºC will be

The ratio of the slopes of P-V diagrams of adibatic and isothermal processes is

Raman got Nobel prize in Physics for

A body of mass 2 kg makes an elastic collision with another body at rest and continues to move in the original direction with one fourth of its original speed. The mass of the second body which collides with the first body is

When a source of light is receding away from an observer, then the spectral lines will get displaced towards

A planet in a distant solar system is 10 times more massive than the earth and its radius is 10 times smaller . Given that the escape velocity from the earth is 11 kms⁻¹, the escape velocity from the surface of the planet would be