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

Which one of the following is TRUE in photoelectric emission?

The following graph shows the stopping potential V₀ versus frequency v for photoelectric emission from two metals A and B. The slope of each of the lines gives ______

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

Two identical bar magnets each of magnetic moment M, separated by some distance are kept perpendicular to each other. The magnetic induction at a point at the same distance d from the centre of magnets, is (µ₀ = permeability of free space)

When a photon enters glass from air, which one of the following quantity does not change?

A potentiometer wire is 4m long and potential difference of 3V is maintained between the ends. The emf of the cell, which balances against a length of 100 cm of the potentiometer wire is ____________.

For a particle performing SHM when displacement is x, the potential energy and restoring force acting on it is denoted by E and F, respectively. The relation between x, E and F is ____________.

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)

A transverse wave is described by the equation, y = Y₀ sin 2π(ft - `"x"/lambda`). The maximum particle velocity is equal to four times the wave velocity if ______

A thermodynamic system goes from states (i) P, V to 2P, V  (ii) P, V to P, 2V. The work done in the two cases is ______.

The graph of stopping potential `"V"_"s"` against frequency v of incident radiation is plotted for two different metals P and Q as shown in the graph. Φ_P and Φ_Q are work-functions of P and Q respectively, then

When light falls on a metal surface, the maximum kinetic energy of the emitted photoelectrons depends upon ______

If the maximum kinetic energy of emitted electrons in photoelectric effect is 3.2 × 10^-19 J and the work-function for metal is 6.63 × 10^-19 J, then stopping potential and threshold wavelength respectively are
[Planck's constant, h = 6.63 × 10³⁴ J-s]
[Velocity of light, c = 3 × 10⁸ `"m"/"s"`]
[Charge on electron= 1.6 × 10^-19 C]

Two cells having unknown emfs E₁ and E₂ (E₁ > E₂) are connected in potentiometer circuit, so as to assist each other. The null point obtained is at 490 cm from the higher potential end. When cell E₂ is connected, so as to oppose cell E₁, the null point is obtained at 90 cm from the same end. The ratio of the emfs of two cells `("E"_1/"E"_2)` is ______.

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)

A 10 m long wire of resistance 20 Q is connected in series with a battery of emf 3 V and a resistance of 10 Ω. The potential gradient along the wire in V/m is ________.

A domain in a ferromagnetic substance is in the form of a cube of side 1 µm. If it contains 8 × 10¹⁰ atoms and each atomic dipole has a dipole moment of 9 × 10^-24 Am² then the magnetisation of the domain is ______.

For a paramagnetic substance, the magnetic susceptibility is ______.

In a series LCR circuit R = 300 Ω, L = 0.9 H, C = 2µF, ω = 1000 rad/s. The impedance of the circuit is ______.

In a series LCR circuit R = 300 Ω, L = 0.9 H, C = 2µF, ω = 1000 rad/s. The impedance of the circuit is ______.