List of top Physics Questions

The stress-strain graph of two wires A and B is shown in the figure. If \(Y_A\) and \(Y_B\) are Young’s moduli of materials of wires A and B respectively, then
stress strain
The angular velocity of a body changes from \(6 \, \text{rad/s}\) to \(21 \, \text{rad/s}\) in a time of \(1.5 \, \text{s}\). If the moment of inertia of the body is \(100 \, \text{g m}^2\), then the rate of change of angular momentum of the body is
Two bodies of masses \( M \) and \( 4M \) initially at rest, start moving towards each other due to their mutual attraction. The velocity of their centre of mass when the first body attains a velocity \( v_0 \) is
If two bodies A and B are projected with same velocity but with different angles \( \theta_1 \) and \( \theta_2 \) respectively with the horizontal such that both will have same range, then the ratio of times of flight of the bodies A and B is
If a force \( \vec{F} = (3\hat{i} + 2\hat{j} + 5\hat{k})~\text{N} \) acting on a body displaces it through \( \vec{d} = (2\hat{i} + 2\hat{j} + 1\hat{k})~\text{m} \), then the work done by the force on the body is
A body falls freely on to a hard horizontal surface. If the coefficient of restitution between the surface and the body is \( 0.8 \), then the ratio of the maximum height to which the body rises after second impact and the initial height of the body is
If the displacement \( s \) (in metre) of a moving particle in terms of time \( t \) (in second) is \( s = t^3 - 6t^2 + 18t + 9 \), then the minimum velocity attained by the particle is
In a common emitter transistor amplifier the resistance of collector is 3 kΩ. If the current amplification factor is 100 and the base resistance is 2 kΩ, then the power gain of the transistor is
The layer of the atmosphere that reflects low frequency (LF) electromagnetic waves during daytime only is
If a 10 W bulb emits electromagnetic waves uniformly in all directions, then the intensity of light at a distance 0.5 m from the source is nearly
The ratio of de Broglie wavelengths associated with thermal neutrons at temperatures 127°C and 352°C is
The ratio of the time periods of the revolution of the electrons in the second and third excited states of hydrogen atom is
In the given options, the diode that is forward biased is
When current in a coil changes from 2 A to 5 A in a time of 0.3 s, if the emf induced in the coil is 40 mV, then the self-inductance of the coil is
If the surface areas of two nuclei are in the ratio 9 : 49, then the ratio of their mass numbers is
The readings of the voltmeter and ammeter in the circuit shown in the diagram are respectively
readings of the voltmeter and ammeter
A capacitor of capacitance 2 μF is charged with the help of a 60 V battery. After disconnecting the battery, if this capacitor is connected in parallel with another uncharged capacitor of capacitance 1 μF, then the potential difference across the plates of the 2 μF capacitor is
The magnetic field at the center of a long solenoid having 400 turns per unit length and carrying a current $I = 6.24 \times 10^{-7$ A is}
If a proton of kinetic energy 8.35 MeV enters a uniform magnetic field of 10 T at right angles to the direction of the field, then the force acting on the proton is
When two identical batteries of internal resistance 1 Ω each are connected in series across a resistor R, the rate of heat produced in R is P1. When the same batteries are connected in parallel across R, the rate of heat produced is P2. If P1 = 2P2, then the value of R is
If the rms speed of the molecules of a diatomic gas at a temperature of 322K is 2000 m/s, then the gas is
A narrow slit of width 2 mm is illuminated with monochromatic light of wavelength 500 nm. If the distance between the slit and the screen is 1 m, then first minima are separated by a distance of
The equation of a transverse wave propagating along a stretched string of length 80 cm is $y = 1.5 \sin ( (5 \times 10^3)x + 20t )$, here 'x' and 'y' are in cm and the time 't' is in seconds. If the mass of the string is 3 g, then the tension in the string is
When an object is placed in front of a convex mirror at a distance 'u' from the pole of the mirror such that the size of the image is 'n' times that of the object, then the object distance 'u' is
The force between two conducting spheres of same radius having charges +8 μC and -4 μC separated by some distance in air is F. If the spheres are connected by a conducting wire and after some time the wire is removed, then the magnitude of the force between the two conducting spheres is