Class 12 - Physics Mock Tests

A particle of mass m and charge -q moves in a circular orbit around an infinitely long line charge with linear charge density λ. The electric field at distance r from the line is E = λ/(2πε₀r). Applying Bohr quantization of angular momentum, the speed v_n of the particle in the n-th orbit is proportional to:

A metallic rod of length L and area of cross-section A is heated by temperature T. If the rod is constrained from expanding, the thermal force developed is: (Y = Young modulus, α = coefficient of linear expansion)

A projectile is launched with an initial velocity of 50 m/s at an angle of 30° to the horizontal. The maximum height reached by the projectile is: (Take g = 10 m/s²)

A conducting rod of length l moves with velocity v perpendicular to a uniform magnetic field B. The induced emf between the ends of the rod is:

In a double-slit experiment, the fringe width is 0.5 mm. If the wavelength is doubled and the slit separation is halved, the new fringe width is:

A particle moves in one dimension with acceleration a = −kv where v is the velocity and k is a constant. If the initial velocity is v₀, the particle comes to rest after time:

A Carnot engine operates between a hot reservoir at T_h = 600 K and a cold reservoir at T_c = 300 K. If the temperature of the cold reservoir is lowered to 150 K while T_h remains unchanged, the new efficiency of the engine is:

A projectile is launched with initial velocity u at an angle θ to the horizontal. The time of flight is: