List of top Physics Questions

Find the final intensity of light (\(I''\)), if the angle between the axes of two polaroids is \(60^\circ\). 

The combination of gates shown below yields: 

For a CE transistor amplifier, the audio signal voltage across the collector resistance of \(2.0\,\text{k}\Omega\) is \(2.0\,\text{V}\). Suppose the current amplification factor of the transistor is 100. What should be the value of \(R_B\) in series with \(V_{BB}\) supply of \(2.0\,\text{V}\) if the base current has to be 10 times the signal current?
A nucleus of uranium decays at rest into nuclei of thorium and helium. Then:
Let binding energy per nucleon of nucleus be denoted by \(E_{bn}\) and radius of nucleus be denoted as \(r\). If mass number of nuclei A and B are 64 and 125 respectively then:
If hydrogen atom, an electron jumps from bigger orbit to smaller orbit so that radius of smaller orbit is one-fourth of radius of bigger orbit. If speed of electron in bigger orbit was \(v\), then speed in smaller orbit is:
The magnifying power of a telescope is 9. When it is adjusted for parallel rays, the distance between the objective and the eye piece is found to be 20 cm. The focal length of lenses are:
The angular size of the central maxima due to a single slit diffraction (a = slit width) is:
A coil of 10 turns and resistance \(20\,\Omega\) is connected in series with a battery of resistance \(30\,\Omega\). The coil is placed with its plane perpendicular to a uniform magnetic field of induction \(10^{-2}\,\text{T}\). If it is now turned through an angle of \(60^\circ\) about an axis in its plane, the charge induced in the coil is (Area of coil \(=10^{-2}\,\text{m}^2\)):
Resolving power of a telescope will be more, if the diameter of the objective is:
The susceptibility of a magnetism at 300 K is \(1.2 \times 10^{-5}\). The temperature at which the susceptibility increases to \(1.8 \times 10^{-5}\) is:
A narrow beam of protons and deuterons, each having the same momentum, enters a region of uniform magnetic field directed perpendicular to their direction of momentum. The ratio of the radii of the circular paths described by them is:
Voltage and current in an AC circuit are given by \(V = 50\sin(50t)\,\text{V}\) and \(i = 50\sin(50t + \frac{\pi}{3})\,\text{mA}\). The power dissipated in the circuit is:
Two point dipoles \(p\hat{k}\) and \(\frac{p}{2}\hat{k}\) are located at \((0,0,0)\) and \((1\,\text{m},0,2\,\text{m})\) respectively. The resultant electric field due to the two dipoles at the point \((1\,\text{m},0,0)\) is:
Two coaxial non-conducting cylinders of radius \(a\) and \(b\) are separated by a material of conductivity \(\sigma\) and a constant potential difference \(V\) is maintained between them by a battery. The current per unit length flowing from one cylinder to the other is:
Electric field in the region is given by \( \vec{E} = \left(\dfrac{M}{x^3}\right)\hat{i}\). The correct expression for the potential in the region is [assume potential at infinity is zero]:
Two balloons are filled with pure gases and other with air respectively. If the pressure and temperature of these balloons are same, then the number of molecules per unit volume is:
Two particles P and Q describe S.H.M. of same amplitude and same frequency along the same straight line. The maximum distance between the two particles is \(2A\). The initial phase difference between the particles is:
A tunnel is dug through the centre of the earth and a ball is released in it. It executes S.H.M. with time period:
In the kinetic theory of gases, which of these statements is/are true? (i) The pressure of a gas is proportional to the mean speed of the molecules. (ii) The root mean square speed of the molecules is proportional to the pressure. (iii) The rate of diffusion is proportional to the mean speed of molecules. (iv) The mean translational kinetic energy of a gas is proportional to its kelvin temperature.
When a string is divided into three segments of length \(l_1, l_2,\) and \(l_3\), the fundamental frequencies of these three segments are \(v_1, v_2,\) and \(v_3\) respectively. The original fundamental frequency of the string is:
The wavelength of radiation emitted by a body depends upon:
One mole of \(O_2\) gas having a volume equal to \(22.4 \text{ litres}\) at \(0^\circ C\) and 1 atm is compressed isothermally so that its volume reduces to \(11.2 \text{ litres}\). The work done in this process is:
A projectile is fired with a velocity \(u\) making an angle \(\theta\) with the horizontal. What is the magnitude of change in velocity when it is at the highest point?
A person with his hand in his pocket is skating on ice at the rate of \(10 \text{ m s}^{-1}\) and describes a circle of radius \(50 \text{ m}\). What is his inclination to vertical? \((g = 10 \text{ m s}^{-2})\)