List of top Physics Questions

The half-life of a radioactive substance is 10 days. The decay constant is
The work function of a metal depends on
In Young's double-slit experiment, the fringe width is proportional to
In an AC circuit containing only an inductor, the current


The force experienced by a charge $q$ moving with velocity $v$ in a magnetic field $B$ is maximum when the angle between $v$ and $B$ is
The magnetic susceptibility is negative for:
A convex lens of focal length $20 \text{ cm}$ is placed in contact with a concave lens of focal length $40 \text{ cm}$. The power of the combination is
The velocity of electromagnetic waves in vacuum is given by
The self-inductance of a solenoid of length $l$, area of cross-section $A$ and number of turns $N$ is proportional to
According to Ohm's law, the relation between the electric current $I$ and the potential difference $V$ across a conductor is
Three capacitors of capacitances $3\ \mu\text{F}$, $3\ \mu\text{F}$ and $3\ \mu\text{F}$ are connected in series. The equivalent capacitance is
A wire of resistance $R$ is stretched to double its original length. Its new resistance will be
In a Wheatstone bridge, the bridge is balanced when the ratio of the resistances in the four arms satisfies
The magnetic field at the centre of a circular coil of radius $r$ carrying a current $I$ is proportional to
An open organ pipe of length $L$ resonates at its fundamental frequency. The wavelength of the sound wave produced is
The electric potential at a distance $r$ from a point charge $q$ is proportional to
A transverse wave is represented by $y = A \sin(kx - \omega t)$. The maximum particle velocity is
The electrostatic force between two charges $q_1$ and $q_2$ separated by a distance $r$ in vacuum is $F$. If a dielectric medium of dielectric constant $K$ is introduced between them, the new force is
The apparent frequency of a siren increases as the source approaches a stationary observer. This phenomenon is known as
The mean free path of a gas molecule is inversely proportional to
In an isothermal process, which of the following remains constant?
The efficiency of a Carnot engine working between temperatures $127^\circ\text{C}$ and $27^\circ\text{C}$ is
The specific heat capacity of a gas at constant pressure ($C_p$) and at constant volume ($C_v$) are related as
The time period of a simple pendulum of length $l$ is $T$. If its length is increased to $4l$, its new time period will be
The ratio of the stress to the strain within the elastic limit is called