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

A potentiometer wire AB having length L and resistance 12r is joined to a cell D of emf ε and internal resistance r. A cell C having emt `ε/2` and internal resistance 3r is connected. The length AJ at which the galvanometer as shown in the figure shows no deflection is ______.

A beam of light is travelling from region II to region III (see the figure). The refractive index in the region I, II and III are n₀​, `​"n"_0/sqrt2`​​ and `"n"_0/sqrt2`​​ respectively. The angle of incidence θ for which the beam just misses entering region III is ______.

Region I	Region II	Region III
n0	n0`sqrt2`	n0`sqrt2`

A sinusoidal wave travelling in the same direction have amplitudes of 3 cm and 4 cm and difference in phase by `pi/2`. The resultant amplitude of the superimposed wave is ______.

A beaker contains water up to a height h₁​ and kerosene of height h₂​ above water, so that the total height of (water + kerosene) is (h₁ ​+ h₂​). Refractive index of water is μ₁​ and that of kerosene is μ₂​. The apparent shift in the position of the bottom of the beaker when viewed from above is ______.

The motion of a particle varies with time according to the relation y = a sin ω t + a cos ω t. Then, ______. 

A ball is dropped from a height of 20 m above the surface of water in a lake. The refractive index of water is `4/3`. A fish inside the lake, in the line of fall of the ball is looking at the ball. At an instant, when the ball is 12.8 m above the water surface, the fish sees the speed of ball as ______.

The graph of kinetic energy against the frequency v of incident light is as shown in the figure. The slope of the graph and intercept on X-axis respectively are ______.

How the linear velocity 'v' of an electron in the Bohr orbit is related to its quantum number 'n'?

The radius of electron's second stationary orbit in Bohr's atom is R. The radius of the third orbit will be ______

The ratio of speed of an electron in the ground state in the Bohr's first orbit of hydrogen atom to velocity of light (c) is ____________.

(h = Planck's constant, ε₀ = permittivity of free space, e = charge on electron)

Light entering an air glass (µ = 1.5) boundary is partly reflected and partly refracted. If the incident and reflected rays are at right angles to each other, the angle of refraction r is given by ____________.

Using Bohr's model, the orbital period of electron in hydrogen atom in nth orbit is (ε₀ = permittivity of free space, h = Planck's constant, m = mass of electron and e = electronic charge)

The Brewster's angle for the glass-air interface is (54.74)°. If a ray of light passing from air to glass strickes at an angle of incidence 45°, then the angle of refraction is ______.
`[tan (54.74)° = sqrt2, sin 45 = 1/sqrt2]`

Bohr model is applied to a particle of mass 'm' and charge 'q' is moving in a plane under the influence of a transverse magnetic field 'B. The energy of the charged particle in the nth level will be (h = Planck's constant).

The wavelength of the first line in Balmer series in the hydrogen spectrum is 'λ'. What is the wavelength of the second line in the same series?

A clock pendulum having coefficient of linear expansion. α = 9 × 10^-7/°C^-1 has a period of 0.5 s at 20°C. If the clock is used in a climate, where the temperature is 30°C, how much time does the clock lose in each oscillation? (g = constant)

When photons of energy hv fall on a metal plate of work function 'W₀', photoelectrons of maximum kinetic energy 'K' are ejected. If the frequency of the radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be ______.

The average K.E. of hydrogen molecules at 27° C is E. The average K.E. at 627° C is ____________.

With the increase in principal quantum number, the energy difference between the two successive energy levels ____________.

A ring of mass m and radius r rotates about an axis passing through its centre and perpendicular to its plane with angular velocity `omega`. Its kinetic energy is ______.