MAH-MHT CET (PCM/PCB) entrance exam Question Bank Solutions for Physics

A pure semiconductor has equal electron and hole concentration of 10¹⁶ m^-3. Doping by indium increases nh to 5 × 10²² m^-3. Then, the value of n_e in the doped semiconductor is ______.

A long straight wire in the horizontal plane carries a current of 75 A in north of south direction, magnitude and direction of field B at a point 3 m east of the wire is ______.

A transverse wave is represented by y = A sin (ωt - kx). For what value of the wavelength is the wave velocity equal to the maximum particle velocity?

If `vec"A"=3hat"i"-2hat"j"+hat"k",vec"B"=hat"i"-3hat"j"+5hat"k" and vec"C"=2hat"i"+hat"j"-4hat"k"` form a right angled triangle then out of the following which one is satisfied?

A bomb at rest explodes into 3 parts of the same mass. The momentum of the two parts is `-3"P"hat"i"` and `2"P"hat"J"` respectively. The magnitude of the momentum of the third part is ______.

A particle is performing SHM starting extreme position, graphical representation shows that between displacement and acceleration there is a phase difference of ______.

A particle performs linear SHM at a particular instant, velocity of the particle is 'u' and acceleration is a while at another instant velocity is 'v' and acceleration is 'β (0 < α < β). The distance between the two position is ______.

A simple pendulum with a bob of mass m and conducting wire of length L swings under gravity through an angle θ. The component of the earth's magnetic field in the direction perpendicular to the swing is B. Maximum emf induced across the pendulum is ______.

(g = acceleration due to gravity)

The increase in internal energy of 1 kg of water at 100°c when it is converted into steam at the same temperature and at 1 atmospheric pressure will be ______.

(density of steam is 0.6 kg m^-3, latent heat of vaporisation of water = 2.25 × 10⁶ J kg^-1).

In figure, a particle is placed at the highest point A of a smooth sphere of radius r. It is given slight push and it leaves the sphere at B, at a depth h vertically below A, such that h is equal to ______.

A spring of force constant of 400 N/m is loaded with a mass of 0.25 kg. The amplitude of oscillations is 4 cm. When mass comes to the equilibrium position. Its velocity is ______.

A particle of mass 5 kg moves in a circle of radius 20 cm. Its linear speed at a time t is given by v = 4t, t is in the second and v is in ms^-1. Find the net force acting on the particle at t = 0.5 s.

The displacement of a particle of mass 3 g executing simple harmonic motion is given by Y = 3 sin (0.2 t) in SI units. The kinetic energy of the particle at a point which is at a distance equal to `1/3`​ of its amplitude from its mean position is ______.

A body of mass 0.5 kg travels in a straight line with velocity v = ax^3/2 where a = 5 m^–1/2s^–1. The change in kinetic energy during its displacement from x = 0 to x = 2 m is ______.

If a gas is compressed adiabatically:

A semicircular wire of radius a having λ as charge per unit length is shown in the figure. Find the electric potential at the centre of the semicircular wire. 

In the given figure, a = 15 m/s² represents the total acceleration of a particle moving in the clockwise direction on a circle of radius R = 2.5 m at a given instant of time. The speed of the particle is ______.

Two wires of different materials have same length L and same diameter d. The second wire is connected at the end of the first wire and forms one single wire of double the length. This wire is subjected to stretching force F to produce the elongation l. The two wires have ______.

When wavelength of light used in optic I instruments A and Bare 4500 Å and 6000 Å respectively, the ratio of resolving pow of A to B will be ______.

Which of the following instruments is not a direct reading instrument?