List of top Physics Questions

A long solenoid has $200$ turns per cm and carries a current $i$. The magnetic field at its centre is $6.28 \times 10^{-2}$ weber/$m^2$. Another long solenoid has 100 turns per cm and it carries a current $i/3$. The value of the magnetic field at its centre is:

A lens is made of flint glass (refractive index $=1.5$ ). When the lens is immersed in a liquid of refractive index $1.25$, the focal length :

A large ship can float but a steel needle sinks because of:

An object is kept on a smooth inclined plane of 1 in $l$. The horizontal acceleration to be imparted to the inclined plane so that the object is stationary relative to the incline is

Which of the following expressions is that of a harmonic progressive wave?

A point source emits sound equally in all directions in a non-absorbing medium. Two point P and Q are at distances of 2 m and 3 m respectively from the source. The ratio of the intensities of the waves at P and Q is

If $E$ = energy, $G$ = gravitational constant, $I$ = impulse and $M$ = mass, the dimensions of $\frac{GIM^{2}}{E^{2}}$ are same as that of

Two parallel large thin metal sheets have equal surface charge densities $\left(\sigma=26.4\times10^{-12} c m^{2}\right)$ of opposite signs. The electric field between these sheets is

A hole is in the bottom of the tank having water. If total pressure at the bottom is $3$ atm $(1 \,atm = 10^{5}\, Nm^{-2})$, then velocity of water flowing from hole is

The length, breadth and thickness of a block are given by I= 12 cm, b = 6 cm and t = 2.45 cm. The volume of the block according to the idea of significant figures should be

Acceleration due to gravity at earth's surface is g $ms^{-2}$ Find the effective value of gravity at a height of 32 km from sea level $(R_e = 6400\, km)$

Two waves, represented by the following equations, are travelling in the same medium $\hspace30mm y_1 = 5 sin \, 2 \pi (75 t - 0.25 x)$ $\hspace30mm y_2 = 10 sin \, 2 \pi (150 t - 0.50 x)$ The intensity $\frac{I_2}{I_1}$ of two waves is

A body is just being revolved in a vertical circle of radius R with a uniform speed. The string breaks when the body is at the highest point. The horizontal distance covered by the body after the string breaks is

A judo fighter in order to throw his opponent on to the mat tries to initially bend his opponent and then rotate him around his hip. As the mass of opponent is brought closer to the fighter?s hip, the force required to throw the opponent is reduced.

An amplifier has a voltage gain $A_{v}=1000$. The voltage gain in $dB$ is :

${ }_{92}^{238} U$ has $92$ protons and $238$ nucleons. It decays by emitting an alpha particle and becomes:

If a street light of mass $M$ is suspended from the end of a uniform rod of length $L$ in different possible patterns as shown in figure, then :

When a $p-n$ junction diode is reverse biased, then

Two spheres of same size, one of mass $2\, kg$ and another of mass $4 \,kg$, are dropped simultaneously from the top of Qutab Minar (height $=72\, m$ ). When they are $1 \,m$ above the ground, the two spheres have the same :

A leaf which contains only green pigments, is illuminated by a laser light of wavelength $0.6328\, \mu m$. It would appear to be :

A boat at anchor is rocked by waves whose crests are $100\, m$ apart and velocity is $25\, m/\sec$. The boat bounces up once in every

In refraction, light waves are bent on passing from one medium to the second medium, because in the second medium

After 2 h $\frac{1}{16} th $ of initial amount of a certain radioactive isotope remains undecayed. The half-life of the isotope is

$10\, g$ of ice at $0^{\circ}\,C$ is mixed with $100\, g$ of water at $50^{\circ}\,C$. What is the resultant temperature of mixture?

A bomb explodes on the moon. How long will it take for the sound to reach the earth?