MHT - CET MCQ

A semiconductor diode rectifier ______.

Most excited states of an atom have life times of about ____________.

A coil of 16 mH and a capacitor of 10 µF are in series with an A.C source along with 5 `Omega` resistances. If inductive reactance is equal to capacitive reactance, then the angular frequency (in rad/s) of source is ____________.

A parallel plate air condenser of capacity 10 µF is charged to a potential of 1000 V. The energy of the condenser is ______

The capacity of pure capacitor is 1 farad. What will be its effective resistance in D.C. circuit?

When the number of turns in a coil is tripled without any change in the length of the coil, its self-inductance ______

A solenoid of 1.5 m length and 4 cm diameter possesses 20 turns per m. A current of 6 A is flowing through it. The magnetic induction at axis inside the solenoid is ____________.

Two long parallel wires, separated by a distance R have equal current I flowing in each of them. The magnetic field of one exerts a force F on the other. The distance R is increased to 4R and the current in each wire is reduced from I to I/4. What is the force between them now?

When the magnetic dipole is rotated through angle `theta`, work done in rotating dipole is given by -mB cos `theta`. Now, a magnetic needle lying parallel to a magnetic field requires W units of work to tum it through 60°. What will be the value of torque needed to maintain the needle in same position?

A small cylindrical soft iron piece is kept in a galvanometer so that

The deflection in a moving coil galvanometer is reduced to half when it is shunted with 'X' `Omega` coil. The relation between 'X' and resistance of galvanometer 'G' is ______.

Which of the following has largest resistance?

The current drawn from the battery in the given network is ______(Internal resistance of the battery is neglected)
 

The length of a potentiometer wire is L. A cell of e.m.f E is balanced at length L/3 from the positive end of the wire. If the length of wire increases by L/2, then the same cell will give balance point at length ____________.

In the meter bridge experiment, a null point was obtained at a distance of ℓ from the left end. The values of resistances in the left and right gaps are doubled and then interchanged. The new position of a null point is ______

The current which flows in a galvanometer of Wheatstone bridge is directly proportional to ______

An electric dipole has a fixed dipole moment `vec "p"`, which makes angle `theta` with respect to x-axis. When subjected to an electric field `vec"E"_1 = "E"hat"i"`, it experiences a torque `vec "T"_1 = tau hat"k"`. When subjected to another electric field `vec "E"_2 = sqrt3 "E"_1 hat "j"` it experiences torque `vec "T"_2 = ~ vec "T"_1` The angle `theta` is ____________.

The first minimum of a single slit diffraction pattern is observed at angle 2° with a light of wavelength 510 nm. The width of this slit is ____________.

Two identical light waves having phase difference 'Φ' propagate in same direction. When they superpose, the intensity of the resultant wave is proportional to ______.

If we study the vibration of a pipe open at both ends, then which of the following statements is not true?

The equation of a stationary wave is given by 2 sin `((pi"x")/15) "cos" (48 pi"t").`The distance between a node and its next antinode is ____________.

A conductor in the fom1 of a right angle `\triangle` ABC with AB = 3 cm and BC = 4 cm carries a current of 15 A. There is a uniform magnetic field of 8 T perpendicular to the plane of the conductor. The force on the conductor will be ______.

A particle starting from the mean position performs linear S.H.M. Its amplitude is 'A' and total energy is 'E'. At what displacement its kinetic energy is 3E/4?

A blackbody emits radiations of maximum intensity at a wavelength of 6000 A, when the temperature of the body is 1227 °C. If the temperature of the body is increased by 2227 °C, the maximum intensity of emitted radiation would be observed at ______.

According to the assumptions made in the kinetic theory of gases, when two molecules of a gas collide with each other, then ______.

A capillary tube when immersed vertically in a liquid records a rise of 6 cm. If the tube is immersed in the liquid at an angle of 60° with the vertical, then length of the liquid column along the tube will be ______.

Detergents in hot water enable grease to be removed from the dishes by ____________.

If a million tiny droplets of water of the same radius coalesce into one larger drop, then the ratio of the surface energy of the large drop to the total surface energy of all the droplets will be ____________.

A water drop of radius R' splits into 'n' smaller drops, each of radius 'r'. The work done in the process is ______.

T = surface tension of water

A stone of mass m tied to a string of length `l` is rotating along a circular path If the torque on the stone is zero, then ____________.

The moment of inertia of a uniform square plate about an axis perpendicular to its plane and passing through the centre is `"Ma"^2/6` where M is the mass and 'a' is the side of square plate. Moment of inertia of this plate about an axis perpendicular to its plane and passing through one of its corner is ______.

A particle is performing vertical circular motion. The difference in tension at lowest and highest point is ______.

A particle of mass m and charge q is placed at rest in a uniform electric field E and then released, the kinetic energy attained by the particle after moving a distance y will be ______.

Pick the wrong answer in the context with rainbow.

The velocity of sound at 0 °C is v0. What will be its velocity at 819 °C?

A piece of lead weighing 500 g gives out 1200 calories of heat when it is cooled from 100° C to 20° C. Find its specific heat.

At what height h above earth, the value of g becomes `g/2` (where R = radius of earth)?

When the value of acceleration due to gravity 'g' becomes `(g/3)` above the earth's surface at height 'h' then relation between 'h' and 'R' is ______.

R =radius of the earth

A body of mass 9 kg is under a force that causes displacement in it given by s = `5t^2"/"6` metre where t is time. The work done by the force in 2 seconds is ______

A mass 'm' is tied to one end of a spring and whirled in a horizontal circle with constant angular velocity. The elongation in the spring is 1 cm. If the angular speed is doubled, the elongation in the spring is 6 cm. The original length of the spring is ______.