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

Two spheres 'S₁' and 'S₂' have same radii but temperatures T₁ and T₂ respectively. Their emissive power is same and emissivity is in the ratio 1: 4. Theo the ratio of T₁ to T₂ is ______.

Two spheres 'S₁' and 'S₂' have radii 'R' and '3R', temperature 'T' K and. `"T"/3` K respectively. If 3 they are coated with a material of same emissivity, rate of radiation of 'S₁'  is E then rate of radiation of ' S₂' is ______.

(spheres are of the same material)

The direction of angular momentum of particle is ____________.

If the emissive and absorptive powers of a body are E and A respectively at temperature T, then the emissive power of a blackbody will be ____________.

A set of 56 tuning forks are arranged in series of increasing frequencies. If each fork gives 4 beats with preceding one and the frequency of the last is twice than than that of first, then frequency of the first fork is ____________.

The magnifying power of a telescope is high if its objective and eyepiece have respectively ______.

An electron of mass 'm' revolving around the nucleus in a circular orbit of radius 'r' has angular momentum 'L'. The magnetic field produced by the electron at the centre of the orbit is e = electric charge, µ₀ = permeability of free space ____________.

A soap bubble is blown such that its diameter increases from 'd' to 'D'. The amount of work done is ______.

(T = surface tension of soap solution)

A soap bubble of radius 'R' is blown. After heating the solution, a second bubble of radius '2R' is blown. The work required to blow the second bubble in comparison to that required for the first bubble is ______.

The excess pressure inside the first soap bubble of radius 'R₁' is two times, that inside the second soap bubble of radius 'R₂'. The ratio of volumes of the first bubble to that of second bubble is ______.

A pipe closed at one end has a length of 1m and at its open end, 0.25 m long uniform string is vibrating in its third harmonic and resonates with a fundamental frequency of pipe. If the tension in the string is 100 N and the speed of sound is 340 `m/s`, then the mass of the string is near ______ 

A pipe open at both ends has a length of 1m. The air column in the pipe can not resonate for a frequency (Neglect end correction, speed of sound in air = 340 m/s)

Two identical wires are vibrating in unison. If the tension in one of the wires is increased by 2%, five beats are produced per second by the two vibrating wires. The initial frequency of each wire is ______

`(sqrt(1 . 0.2) ≑ 1 . 0.1)`

When sunlight is scattered by atmospheric atoms and molecules, the amount of scattered light, of wavelength 440 nm, is 'I'. What amount of light of wavelength 660 nm will be scattered?

A simple microscope is used to see the object first in blue light and then in red light. Due to the change from blue to red light, what is the effect on its magnifying power?

Two wires are producing fundamental notes of the same frequency. Change in which of the following factors of one wire will NOT produce beats between them?

A particle is revolving in anticlockwise sense along the circumference of a circle of radius 'r' with linear velocity 'v', then the angle between 'v' and angular velocity 'ω' will be ______.

S.I. Unit of emissive power of a body at a given temperature is ______.

A black sphere has radius 'R' whose rate of radiation is 'E' at temperature 'T'. If radius is made `R/3`and temperature '3T', the rate of radiation will be ______.

If E, M and P are the kinetic energy, mass and linear momentum of a particle respectively, which of the following relations represents the angular momentum L of the particle when the particle rotates in a circle of radius R?