List of top Physics Questions

The effective acceleration of a body, when thrown upwards with acceleration $ a $ will be:

The temperature $(T )$ dependence of resistivity $(r)$ of a semiconductor is represented by

Sodium lamps are used in foggy conditions because

A circular coil of radius $R$ carries an electric current. The magnetic field due to the coil at a point on the axis of the coil located at a distance $r$ from the center of the coil, such that $r > > R$, varies as

A sphere of mass $M$ and radius $R$ is falling in a viscous fluid. The terminal velocity attained by the falling object will be proportional to

A proton and an $\alpha$ - particle, moving with the same velocity, enter into a uniform magnetic field, acting normal to the plane of their motion. The ratio of the radii of the circular paths described by the proton and $\alpha$ - particle is

Two long conductors, separated by a distance d carry current $I_1$ and $I_2$ in the same direction. They exert a force $F$ on each other. Now the current in one of them increased to two times and its direction reversed. The distance is also increased to $3d$. The new value of the force between them is

In a step-up transformer ratio of number of turns in primary to seconday coil is $1: 25 .$ If input voltage is $230$ volt and load current is $2 \,amp$, then current in primary is :

For a transistor amplifier in common emitter configuration having load impedance of $1\, kO$ ($h_{fe} = 50$ and $h_{oe} = 25$) the current gain is

When the glancing angle of incidence of light on a material is 30$^\circ$, the reflected and refracted light are found to be perpendicular. The refractive index of material is

Two waves having intensity ratio 25 : 4 produce interference. The ratio of maximum to minima intensity is

Two vectors have magnitudes 3 and 5. If angle between them is 60$^{\circ}$, then the dot product of two vectors will be

The volume of a metal sphere increases by $ \text{0}\text{.15 }\!\!%\!\!\text{ } $ when its temperature is raised by $ \text{24}{{\,}^{\text{o}}}\text{C}\text{.} $ The coefficient of linear expansion of metal is:

The relative permeability of iron is $6000$. Its magnetic susceptibility is

As shown in figure, a planet revolves in elliptical orbit around the sun. Where is KE of the planet maximum?

The period of SHM of a particle is 12 s. The phase difference between the positions at $ t=3\,s $ and $ t=4s $ will be:

A triode valve has an amplification factor of 20 and its plate is given a potential of 300 V. The grid-voltage to reduce the plate current to zero, is :

For a satellite moving in an orbit around the earth, the ratio of kinetic to potential energy is:

In an ideal parallel LC circuit, the capacitor is charged by connecting it to a DC source which is then disconnected. -The current in the circuit:

A wire elongates by $ l \,mm$ when a load w is hanged from it. If the wire goes over a pulley and two weights w each are hung at the two ends, the elongation of the wire will be (in mm):

A body of mass $M$ moves with velocity $v$ and collides elastically with another body of mass $m$ $(M \gg>m)$ at rest, then the velocity of body of mass $m$ is :

If torque is zero then:

A solid sphere, a hollow sphere and a disc having same mass and radius roll down the same inclined plane from rest. Which one will reach the ground in least time?

If the momentum of body is increased by $100\%$, then the percentage increase in the kinetic energy will be: