List of practice Questions

The working principle of atom bomb
In a transistor connected in CE configuration, the emitter current increases from 10 mA to 20 mA when the base current increases from 0.12 mA to 0.24 mA. Then the current gain is
The p-n junction which generates an emf when the solar radiation incidents on it is
The waves that are used for line-of-sight (LOS) communication are
The number of radial and angular nodes of 4f orbital respectively are

In the given circuit, if the cell delivers maximum power to the circuit, then value of $R$ is

In a galvanometer, when the number of turns $N$ becomes $2N$ and resistance $R$ becomes doubled, then
Among the following, the quantity that is termed as gyro magnetic ratio is (Given: $m_e$ = mass of electron, $e$ = charge of electron)
Core of electromagnets are made of materials which have the properties
The ratio of the flux-linkage to current is
The AC current in a circuit is given by $3 \sin(\omega t)$ amperes. The time taken by the current to drop from RMS value to zero is
The electric field of an electromagnetic wave propagating in vacuum is given by $E = 35 \cos(kx - 4.5 \times 10^8 t)$ where $E_x$ and $t$ are in V/m and s respectively. The magnitude of the propagation vector $k$ is
A wave is reflected from a rigid support. The change in phase on reflection will be
The colour which has the highest critical angle of incidence is
For a wavelength 670 nm of light coming from a galaxy moving with velocity $V$, the observed wavelength is 670.7 nm. The value of $V$ is
A conducting sphere of radius 5 cm has an unknown charge. The electric field at 10 cm from the center of the sphere is $1.8 \times 10^3$ N/C. The net charge on the sphere is

The figure shows a part of a circuit. The voltage across A and B is 4V. Then the voltages across 2 $\mu$F and 1.5 $\mu$F are respectively

Two equipotential surfaces A and B are separated by a distance x. The work done in moving a charge -q from A to B is (Assume $\varepsilon_0$ = permittivity of free space)

In the given circuit, the potential difference between B and D is zero. Then the value of the current I is

A liquid of density 800 kg/m$^3$ is used instead of mercury in the Torricelli barometer. What is the height of the liquid column if atmospheric pressure is 76 cm of Hg? (Density of mercury = $13.6 \times 10^3$ kg/m$^3$)
If $\Delta Q$ is the heat supplied and $\Delta W$ is the work done by the gas at constant pressure, then the ratio $\dfrac{\Delta Q}{\Delta W}$ is ($\gamma$ = specific heat ratio)
A Carnot's engine can have 100% efficiency if the temperature of the sink is

A gas is taken through the cycle A → B → C → A as shown in the figure. The net work done by the gas after one cycle is

The number of rotational degrees of freedom of a diatomic molecule is
The power of an engine which draws 1000 kg of water from a well of depth 9 m in one minute is (acceleration due to gravity $g = 10$ m/s$^2$)