List of practice Questions

When a number of small droplets combines to form a large drop, then
With what minimum acceleration can a fireman slide down a rope while breaking strength of the rope is $\frac23$ of the weight?
A stone is thrown at an angle to the horizontal reaches a maximum height H. Then the time of flight of stone will be
Two parallel plates of area A are separated by two different dielectrics as shown in figure. The net capacitance is
Two springs of force constants $k₁$ and $k₂$ are connected as shown. The effective spring constant k is
A body of weight 2 kg is suspended as shown in figure. The tension $T₁$ in the horizontal string (in kg-wt) is
If the momentum of a body is increased by 100%, then the percentage increase in the kinetic energy is
Current in a coil changes from 5 A to 10 A in 0.2 s. If the coefficient of self-induction is 10 H, then the induced emf is
The force of interaction between two charges $q₁=6μ C$ and $q₂=2μ C$ is 12 N. If charge $q=-2μ C$ is added to each of the charges, then the new force of interaction is
The number of turns in primary coil of a transformer is 20 and the number of turns in the secondary is 10. If the voltage across the primary is 220 V, what is the voltage across the secondary?
An electron of an atom transits from $n₁$ to $n₂$. In which of the following, maximum frequency of photon will be emitted?
A rod of length L and mass M is bent to form a semicircular ring as shown in figure. The moment of inertia about XY is
In the figure shown, $m₁=10~kg$, $m₂=6$ kg, $m₃=4~kg$. If $T₃=40~N,$ $T₂=?$}
A string fixed at both ends oscillates in 5 segments, length 10 m and velocity of wave is 20 m/s. What is the frequency?
When the amplitude of a body executing SHM becomes twice what happens?
The time period of a geostationary satellite at a height 36000 km is 24 h. A spy satellite orbits earth at a height 6400 km. What will be the time period of spy satellite? [Radius of the earth = 6400 km]
A bomb of mass 9 kg explodes into two parts. One part of mass 3 kg moves with velocity 16 m/s, then the KE of the other part is
A convex lens is placed between object and a screen. The size of object is 3 cm and an image of height 9 cm is obtained on the screen. When the lens is displaced to a new position, what will be the size of image on the screen?
A gas is suddenly expanded such that its final volume becomes 3 times its initial volume. If the specific heat at constant volume of the gas is 2R, then the ratio of initial to final pressures is nearly equal to
Two pendulums have time periods T and 5T/4. They start SHM at the same time from the mean position. What will be the phase difference between them after the bigger pendulum completed one oscillation?
A body is coming with a velocity of 72 km/h on a rough horizontal surface of coefficient of friction 0.5. If the acceleration due to gravity is $10~m/s²$, find the minimum distance it can be stopped.
A bullet comes out of the barrel of gun of length 2 m with a speed 80 m/s. The average acceleration of the bullet is
A disc of radius 0.1 m is rotating with a frequency 10 rev/s in a normal magnetic field of strength 0.1 T. Net induced emf is
A beam of light is incident at $60^\circ$ to a plane surface. The reflected and refracted rays are perpendicular to each other then refractive index of the surface is
Two wires of lengths l and 2l, radii r and 2r respectively having same Young's modulus are hung with a weight mg. Net elongation is