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

A big water drop is formed by the combination of 'n' small water drops of equal radii. The ratio of the surface energy of 'n 'drops to the surface energy of big drop is ______.

Which of the following quantity does not change due to damping of oscillations?

A disc of radius R and thickness `"R"/6` has moment of inertia/about an axis passing through its centre and perpendicular to its plane. Disc is melted and recast into a solid sphere. The moment of inertia of a sphere about its diameter is ______.

The moment of inertia of a body about a given axis is 1.2 kg-m². Initially, the body is at rest. In order to produce, a rotational kinetic energy of 1500 J, an acceleration of 25 rad/s² must be applied about that axis for a duration of ______.

A straight solenoid has 50 turns per cm in primary and 200 turns per cm in the secondary. The area of cross-section of the solenoid is 4 cm². The mutual inductance is ______.

A power transmission line feeds input power at 2300 V to a stepdown transformer with its primary windings having 4000 turns. What should be the number of turns in the secondary in order to get output power at 230 V?

Three identical blocks A, B and C are placed on horizontal frictionless surface. The blocks A and C are at rest. But A is approaching towards B with a speed 10 m/s. The coefficient of restitution for all collision is 0.5. The speed of the block C just after the collision is ______.

A water-proofing agent changes the angle of contact ______

In an LC circuit ______

The angle of contact for a liquid which wets the surface of a solid is ____________.

Which of the following statements is incorrect?

What is the angle between resultant of A + B and A x B.

What will be the angle of contact of a liquid relative to a solid if forces of adhesion and cohesion are equal?

Each plate of a parallel plate condenser has surface area of 5 cm². The distance between the plates is 2 mm. The dielectric constant of the medium between the plates is 5. Then the capacity of the condenser is ____________.

(`epsilon_0 = 8.85  xx 10^-12 C^2//Nm^2`)

For an ideal gas with initial pressure and volume P_i and V_i respectively, a reversible isothermal expansion happens, when its volume becomes V₀. Then it is compressed to its original volume V_i by a reversible adiabatic process. If the final pressure is P_f then which of the following statements is true?

Above the resonance frequency, ____________.

In a parallel plate air capacitor the distance between plates is reduced to one-fourth and the space between them is filled with a dielectric medium of constant 2. If the initial capacity of the capacitor is 4μF then its new capacity is ______.

A parallel plate capacitor is charged and then disconnected from the charging battery. If the plates are now moved farther apart by pulling them by means of insulating handles, then ______.

Two metal plates are separated by 2 cm. The potentials of the plates are -10 V and + 30 V. The electric field between the two plates is ______.

Figure shows plot of charge versus potential difference for four parallel plate capacitors, which have same plate area, dielectric medium but different distance between the plates. Which one of them have smallest plate distance?