List of top Physics Questions

The force between two small charged spheres having charges of \( 1 \times 10^{-7} \) C and \( 2 \times 10^{-7} \) C placed 20 cm apart in air is:
Electric field in a certain region is given by \( \vec{E} = \left( \frac{A}{x^2} \hat{i} + \frac{B}{y^3} \hat{j} \right) \). The SI unit of A and B are:

A thermodynamic system is taken through a cyclic process as shown in the PV diagram. The total work done in the process is: 

A particle executes Simple Harmonic Motion (SHM) with amplitude \( A \). The distance from the mean position when its kinetic energy becomes equal to its potential energy is:
Draw the energy level diagram for hydrogen atom. Show the transitions of Lyman, Balmer, Paschen, Brackett and Pfund series in the diagram. In which region do these spectrum lie?
What will be the refractive index of a thin prism material if its refracting angle and angle of deviation are the same?
The work done in placing a charge of \( 8 \times 10^{-18} \) coulomb on a capacitor of capacitance 100 microfarad is:
The magnetic moment of an electron (e) revolving in an orbit around the nucleus with an orbital angular momentum is given by:
If 1000 droplets of water of surface tension \( 0.07 \). having same radius 1mm each, combine to from a single drop. In the process the released surface energy is-
(Take \( \pi = \frac{22}{7} \)):
A 100m long wire having cross-sectional area \( 6.25 \times 10^{-4} \, {m}^2 \) and Young's modulus is \( 10^{10} \, {Nm}^{-2} \) is subjected to a load of 250N, then the elongation in the wire will be:
A wire carrying a current I along the positive x-axis has length L. It is kept in a magnetic field \(\vec{B}=(2\vec{i}+3\vec j-4\vec k)T\). The magnitude of the magnetic force acting on the wire is:
When a force \(\overrightarrow F = xy²\hat i + x²y\hat j N\) acts on a particle and moves it along a straight line from the origin to the point (4, 0), the work done is,
The amplitude of a particle executing SHM is $3 \,cm$ The displacement at which its kinetic energy will be $25 \%$ more than the potential energy is:_______ $cm$
Two tuning forks of frequencies 320 Hz and 340 Hz are sounded together to produce sound waves. The velocity of sound in air is 326.4 m/s. Calculate the difference in wavelengths of these waves.
A body of mass 200 g is tied to a spring of spring constant 12.5 N/m, while the other end of the spring is fixed at point \( O \). If the body moves about \( O \) in a circular path on a smooth horizontal surface with constant angular speed 5 rad/s, then the ratio of extension in the spring to its natural length will be:
A horizontal bridge is built across a river. A student standing on the bridge throws a small ball vertically upwards with a velocity \(4\ ms^{-1}\). The ball strikes the water surface after \(4s\). The height of bridge above water surface is
(Take: \(g=10\ ms^{-2}\))
Derive laws of reflection of light using Huygens’ principle.
Ten identical cells each emf 2V and internal resistance 1Ω are connected in series with two cells wrongly connected. A resistor of 10Ω is connected to the combination. What is the current through the resistor?
A full-wave rectifer with diodes D1 and D2 is used to rectify 50 Hz alternating voltage. The diode D1 conducts _______ times in one second.

As shown in figure, a $70 kg$ garden roller is pushed with a force of $\vec{F}=200 N$ at an angle of $30^{\circ}$ with horizontal. The normal reaction on the roller is (Given $g=10 m s ^{-2}$ )

A hypothetical gas expands adiabatically such that its volume changes from 08 litres to 27 litres. If the ratio of final pressure of the gas to initial pressure of the gas is $\frac{16}{B 1}$. Then the ratio of $\frac{C p}{C v}$ will be

The ratio of frequencies of fundamental harmonic produced by an open pipe to that of closed pipe having the same length is:
An ideal mono-atomic gas is adiabatically compressed so that its final temperature is twice its initial temperature. Calculate the ratio of final pressure to its initial pressure.
A 100 \(\Omega\) resistor is connected to a 220 V, 50 Hz supply.
Calculate:
(i) r.m.s. value of current
(ii) net power consumed over the full cycle
Write the differences between intrinsic semiconductor and extrinsic semiconductor.
OR
What is P-N junction diode? Describe its use as a full wave rectifier with diagram.