List of practice Questions

The roots of the equation \( x^4 - 20x^3 + 140x^2 - 400x + 384 = 0 \) are in
If \(1, \alpha_1, \alpha_2, \alpha_3, \ldots, \alpha_{n-1}\) are n roots of the equation, \( x^n = 1 \) then the value of \( (1-\alpha_1)(1-\alpha_2)(1-\alpha_3)\ldots(1-\alpha_{n-1}) \) is
X- rays of wavelength 15 pm are scattered from a target. The wavelength of the X-rays scattered through 60° is (Given compton wavelength = 2.426 pm)
The Rayleigh Jean's Law,
(A) agrees well with experimental results at low frequencies.
(B) agrees well with experimental results at longer. wavelengths.
(C) shows ultra-violet catastrophe at higher frequencies.
(D) agrees well with experimental results at higher frequencies.
Choose the correct answer from the options given below:
The energy radiated per minute from the filament of an incandescent lamp at 2000 K, surface area \( 4 \times 10^{-5} \) m² and relative emittance is 0.85, will be (Given Stefan's constant \( \sigma = 5.7 \times 10^{-8} \) Jm⁻²s⁻¹K⁻⁴)
The ratio of adiabatic to the isobaric coefficient of expansion is
Which of following is correct form of first TdS equation ?
Which of the following orders in a double slit Fraunhofer diffraction pattern will be missing if the slit width is 0.12 mm and slits are 0.6 mm apart?
A zone plate
Work done in compressing adiabatically 1g of air, initially at NTP to one fourth of its original volume is: (take density of air = 0.0001465 g/cm³ and \(\gamma\) = 1.5)
Change of entropy of a perfect gas for isochoric process is
Sunlight is reflected from a material. The reflected light is 100% polarized at a certain instant. Assuming refractive index of material equal to 1.732, the angle between the sun and the horizon at that instant is
In Michelson Interferometer the intensity is expressed as \( 4A^2\cos^2\frac{\delta}{2} \), where \( \delta = \frac{2\pi}{\lambda}(2d \cos\theta) \), d being the distance between Mirrors M₁ and M₂. The intensity is maximum, when \( \delta \) is
Two satellites A and B of mass 'M' are orbiting the earth in circular orbits at altitudes 2R and 5R respectively, where R is the radius of the earth. The ratio of kinetic energies of satellite A and B will be
The condition for bright ring in the Newton's Ring arrangement is (where 't' is thickness of film, m is order and \(\lambda\) is wavelength):
Which of the following is not a characteristic of a laser light?
In order to produce LASER, the correct sequence of processes given below will be
(A) Pumping
(B) Population inversion
(C) Stimulated emission
(D) Light Amplification
Choose the correct answer from the options given below:
If J, E and I are the angular momentum, kinetic energy of rotation and moment of inertia respectively, then which of following is incorrect?
Which of following is true in a LCR circuit?
(A) In purely inductive circuit (R = 0), Quality factor is infinite.
(B) Resistance 'R' is alone responsible for damping of oscillations.
(C) Discharge of capacitor is not oscillatory in character.
(D) Q-factor is measure of sharpness of resonance in case of a driven oscillator.
Choose the correct answer from the options given below:
In a perfectly elastic collision if m₁ and m₂ be the masses and v₁ and v₂ be the velocities of two colliding particles. Then velocity after the collision, if particles stick together will be:
Which of the following is/are correct about conservative and non-conservative forces?
(A) For conservative and non-conservative forces conservation of energy holds good.
(B) Friction is a conservative force.
(C) The work done by a conservative force in a closed path is zero.
(D) Friction is a non-conservative force.
Choose the correct answer from the options given below:
A wave of frequency 500 Hz is travelling with a velocity 1000 m/s. How far are two points situated in wave whose displacement differ in phase by \( \frac{\pi}{3} \)?
Two tuning forks produce 6 beats per second when sounded together. One of the fork is in unison with 1.5 m length of wire and the other with 2.0 m length of wire. The frequencies of forks are:
In common emitter connection, the collector leakage current in a transistor is 300\(\mu\)A. The leakage current in the transistor in common base arrangement will be (Given \(\beta\) = 130):
A power gain of 100 in decibel (db) is: