VITEEE Physics Test - 2 - JEE MCQ

Emission of electrons in the photoelectric effect is possible, if

A sheet of aluminium is inserted in the air gap between the parallel plate capacitor, without touching any the two plates of the capacitor. The capacitance the capacitor is:

When a current is passed through water acidified with a dilute sulphuric acid, the gases formed at the platinum electrodes are

The resistance of a coil at 100^oC is 4.2 Ω. If temperature coefficient of resistance of the coil material is 0.004^oC^-1, then its resistance at 0^oC is

The internal resistance of a cell of e.m.f. 3 V is 0.1 Ω, If it is connected to a resistance of 2.9Ω then voltage across the cell will be

In short wave communication waves of which of the following frequencies will be reflected back by the ionospheric layer having electron density 10¹¹ per m^-3?

When a current flows in a wire, there exists an electric field whose direction is

A particle with a specific charge S is fired with a speed v towards a wall at a distance d, perpendicular to the wall. What minimum magnetic field must exist in this region for particle not hit the wall ?

A generator at a utility company produces 100 A of current at 4000 V. The voltage is stepped up to 240000 V by a transformer before it is sent on a high voltage transmission line. The current in transmission line is

A step-up transformer has transformation ratio of 3:2 What is the voltage in secondary, if voltage in primary is 30 V ?

The coefficient of mutual inductance, when magnetic flux changes by 2 X 10^-2 Wb and current changes by 0.01 A is

A point charge q is placed at a distance a/2 directly above the centre of a square of side a. The electric flux through the square assuming it to be one face of the cube is

Which of the following waves have the maximum wavelength?

A 2 μ F condenser is charged to 500V and then its plates are joined through of consistance. The heat produced in the resistance in joules is

If a point charge q be rotated in a circle of radius r around a charge Q, the work done will be

The electric potential at a point (x, y) in the xy-plane is given by: V=-kxy. The electric field intensity at a distance r from the origin varies as

An electric dipole of dipole moment p is placed in uniform electric field of strength E. If θ is the angle between p and E, then potential energy of the dipole becomes maximum, when θ is

A radioactive element has a half life of 15 years. The fraction that will decay in 30 years is

The photoelectric threshold of a certain metal is 30 Å. If the radiation of 2000 Å is incident on the metal

A double convex lens made of air with both radii of curvature being 10 cm is placed in a medium of refractive index 1.5. The focal length and nature of lens is

In comparison to a half wave rectifier, the full wave rectifier gives lower

If a full wave rectifier circuit is operating from 50 Hz mains, then fundamental frequency in the ripple will be

The current gain for a transistor working as common-base amplifier is 0.96. If the emitter current is 7.2 mA, then the base current is

To obtain electrons as majority charge carriers in a semiconductor, the impurity mixed is