List of top Physics Questions

1 kg of water at 100°C is converted into steam at 100°C by boiling at atmospheric pressure. The volume of water changes from $1.00 \times 10^{-3}\, \text{m}^3$ as a liquid to $1.671 \times 10^{-3}\, \text{m}^3$ as steam. The change in internal energy of the system during the process will be:

The radius of curvature of each surface of a convex lens having refractive index 1.8 is 20 cm. The lens is now immersed in a liquid of refractive index 1.5. The ratio of power of lens in air to its power in the liquid will be:

The magnetic field B crossing normally a square metallic plate of area $ 4 \, \text{m}^2 $ is changing with time as shown in the figure. The magnitude of induced emf in the plate during $ t = 2 \, \text{s} $ to $ t = 4 \, \text{s} $ is _______ mV.

The length of a wire becomes $ l_1 $ and $ l_2 $ when 100 N and 120 N tensions are applied respectively. If $ l_1 = 11 \, \text{l}_0 $, the natural length of the wire will be $ \frac{1}{x} \, l_1 $. Here the value of $ x $ is _____

A monochromatic light is incident on a hydrogen sample in ground state. Hydrogen atoms absorb a fraction of light and subsequently emit radiation of six different wavelengths. The frequency of incident light is $ x \times 10^{15} \, \text{Hz} $. The value of $ x $ is_______

A force $ \mathbf{F} = (2 + 3x) \hat{i})$ acts on a particle in the $ x $-direction where $ F $ is in newton and $ x $ is in meter. The work done by this force during a displacement from $ x = 0 $ to $ x = 4 \, \text{m} $ is _____ J.

As shown in the figure, a configuration of two equal point charges (q₀ = + 2 $\mu$C) is placed on an inclined plane. Mass of each point charge is 20g. Assume that there is no friction between charge and plane. For the system of two point charges to be in equilibrium (at rest) the height $ h = x \times 10^{-3} \, \text{m} $. The value of $ x $ is _____

A solid sphere of mass 500 g and radius 5 cm is rotated about one of its diameter with angular speed of 10 rad/s. If the moment of inertia of the sphere about its tangent is $ x \times 10^2 $ times its angular momentum about the diameter. Then the value of $ x $ will be_____

The equation of wave is given by $ Y = 10^2 \sin 2 \pi \left( (60t - 0.5x + \frac{\pi}{4}) \right) $ where $ x $ and $ Y $ are in m and t in s. The speed of the wave is _____ km h$^{-1}$.

A projectile fired at $30^{\circ}$ to the ground is observed to be at the same height at time 3s and 5s after projection, during its flight. The speed of projection of the projectile is_____ ms$^{-1}$.

Two radioactive elements A and B initially have the same number of atoms. The half-life of A is the same as the average life of B. If $ \lambda_A $ and $ \lambda_B $ are the decay constants of A and B respectively, then choose the correct relation from the given options:

In a Young's double slits experiment, the ratio of amplitude of light coming from slits is 2:1. The ratio of the maximum to minimum intensity in the interference pattern is

A wire of length 'L' and radius 'r' is clamped rigidly at one end. When the other end of the wire is pulled by a force f, its length increases by 'l'. Another wire of same material of length '2L' and radius '2r' is pulled by a force '2f'. Then the increase in its length will be

The ratio of escape velocity of a planet to the escape velocity of earth will be:- Given: Mass of the planet is 16 times mass of earth and radius of the planet is 4 times the radius of earth.

The modulation index for an A.M. wave having maximum and minimum peak-to-peak voltages of 14 mV and 6 mV respectively is:

A child of mass 5 kg is going round a merry-goround that makes 1 rotation in 3.14 s. The radius of the merry-go-round is 2 m. The centrifugal force on the child will be

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : The binding energy per nucleon is practically independent of the atomic number for nuclei of mass number in the range 30 to 170.
Reason R : Nuclear force is short ranged.
In the light of the above statements, choose the correct answer from the options given below:

Match List-I with List-II

	List- I (Layer of atmosphere)		List- II (Approximate height over earth's surface)
A.	F₁-Layer	I.	10 km
B.	D-Layer	II.	170-190 km
C.	Troposphere	III.	100 km
D.	E-layer	IV.	65-75 km

Choose the correct answer from the options given below:

At $300 K$ the rms speed of oxygen molecules is $\sqrt {\frac {\alpha+5}{\alpha}}$ times to that of its average speed in the gas. Then, the value of $\alpha$ will be
(used $\pi=\frac {22}{7}$)

If a radioactive element with a half-life of 30 min undergoes beta decay. The fraction of the radioactive element that remains undecayed after 90 min is:

Match List I with List I:

List I		List II
A	AM Broadcast	I	88-108 MHz
B	FM Broadcast	II	540-1600 kHz
C	Television	III	3.7-4.2 GHz
D	Satellite Communication	IV	54 MHz-890 MHz

Choose the correct answer from the options given below:

The orbital angular momentum of a satellite is L, when it is revolving in a circular orbit at height h from earth surface. If the distance of satellite from the earth centre is increased by eight times to its initial value, then the new angular momentum will be

Two satellites of masses m and 3m revolve around the earth in circular orbits of radii r & 3r respectively. The ratio of orbital speeds of the satellites respectively is

The figure shows a liquid of given density flowing steadily in horizontal tube of varying cross - section. Cross sectional areas at A is 1.5 cm², and B is is 25 mm², if the speed of liquid at B is 60 cm/s then $(P_A-P_B)$ is:
(Given $P_A$ and $P_B$ are liquid pressures at A and B points.
density $ρ = 1000 \space kg \space m^{-3}$
A and B are on the axis of tube)

The ratio of wavelengths of proton and deuteron accelerated by potential $V_p$ and $V_d$ is $1: \sqrt{2}$ Then, the ratio of $V_p$ to $V_d$ will be