List of top Physics Questions

A series combination of $n_1$ capacitors, each of capacity $C_1$ is charged by source of potential difference $4\, V$. When another parallel combination of $n_2$ capacitors each of capacity $C_2$ is charged by a source of potential difference $V$, it has the same total energy stored in it as the first combination has. The value of $C_2$ in terms of $C_1$ is then

Degree of freedom for polyatomic gas

In this circuit, the value of $I_2$, is

In a Wheatstone?s network, $P = 2 \, \Omega , Q = 2\, \Omega , R = 2\, \Omega$ and$ S = 3\,\Omega$. The resistance with which $S$ is to be shunted in order that the bridge may be balanced is

A battery of emf $ 8V $ with internal resistance $ 0.5 \, \Omega$ is being charged by a $ 120 \,V\, d.c. $ supply using a series resistance of $ 15.5 \Omega $ . The terminal voltage of the battery is

For the resistance network shown in the figure, choose the correct option(s).

Consider a copper wire of length $L$, cross-sectional area $A$. It has $n$ number of free electrons per unit volume. Which of the following is the correct expression of drift velocity of the electrons when the wire carries a steady current $I$?

A Wheatstone bridge has the resistances $10\, \Omega,\, 10\, \Omega, 10\, \Omega$ and $30\, \Omega$ in its four arms. What resistance joined in parallel to the $30\, \Omega$ resistance will bring it to the balanced condition?

What current will flow through the $2\,k\Omega$ resistor in the circuit shown in the figure?

If in a voltaic cell, $5\, g$ of zinc is consumed, we will get how many ampere hour? $(ECE$ of zinc is $3.387 \times 10^{-7} kg\, C^{-1})$

It is preferable to measure the e.m.f. of a cell by potentiometer than by a voltmeter because of the following possible reasons. (i) In case of potentiometer, no current flows through the cell. (ii) The length of the potentiometer allows greater precision. (iii) Measurement by the potentiometer is quicker. (iv) The sensitivity of the galvanometer, when using a potentiometer is not relevant. Which of these reasons are correct?

Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurement of the current and the voltage difference are 3% each, then error in the value of resistance of the wire is :

Three resistances of equal values are arranged in four different configurations as shown below. Power dissipation in the increasing order is

Four resistors $A, B, C$ and $D$ form a Wheatstones bridge. The bridge is balanced, when $C=100 \Omega$. If $A$ and $B$ are interchanged, the bridge balances for $C=121 \Omega$. The value of $D$ is

This question has Statement 1 and Statement 2. Of the four choices given after the Statements, choose the one that best describes the two Statements. If two springs $S_1$ and $S_2$ of force constants $k_1$ and $k_2$, respectively, are stretched by the same force, it is found that more work is done on spring $S_1$ than on spring $S_2$. If stretched by the same amount, work done on $S_1$, will be more than that on $S_2$ $k_1 < k_2$

If a simple pendulum has significant amplitude (up to a factor of 1/e of original) only in the period between $t = 0s$ to $t = \tau s$, then $\tau$ may be called the average life of the pendulum. When the spherical bob of the pendulum suffers a retardation (due to viscous drag) proportional to its velocity, with 'b' as the constant of proportionality, the averatge life time of the pendulum is (assuming damping is small)

The simple harmonic vibrations of two particles are $ y_{1} =5$ sin (100$t$) and $y_{2} =4 $ cos $\left(100t +\frac{\pi}{4}\right).$ The phase difference between them is

A cubical region of side a has its centre at the origin. It encloses three fixed point charges, $- q$ at $(0,- \frac{a}{4} ,0), + 3q$ at $(0, 0, 0)$ and $- q$ at $(0,+ \frac{a}{4},0)$. Choose the correct option(s).

An electrostatic field line never form closed loop. Electrostatic field is a conservative field.

The ratio of radius of two bubbles is $2:1$. What is the ratio excess pressure inside them?

A large number of droplets, each of radius, $r$ coalesce to form a bigger drop of radius, $R$. An engineer designs a machine so that the energy released in this process is converted into the kinetic energy of the drop. Velocity of the drop is ($T=$ surface tension, $\rho=$ density)

A charge of total amount $Q$ is distributed over two concentric hollow spheres of radii $r$ and $R (R > r)$ such that the surface charge densities on the two spheres are equal. The electric potential at the common centre is

If a magnet is suspended at an angle $ 30{}^\circ $ to the magnetic meridian, the dip needle makes angle of $ 45{}^\circ $ with the horizontal. The real dip is

Three long, straight parallel wires, carrying current, are arranged as shown in figure. The force experienced by a 25 cm length of wire C is

Two cars of masses $m_1$ and $m_2$ are moving in circles of radii $r_1$ and $r_2$, respectively. Their speeds are such that they make complete circles in the same time $t$. The ratio of their centripetal acceleration is :