List of top Physics Questions

Two stretched strings have lengths $l$ and $2l$ while tension are $T$ and $4T$ respectively. If they are made of same material the ratio of their frequency is
Which one of the following statements is true?
What causes chromatic aberration?
A particle of mass $m$ moves with constant speed along a circular path of radius $r$ under the action of force $F .$ Its speed is
A motor is used to deliver water at a certain rate through a given horizontal pipe. To deliver $n$-times the water through the same pipe in the same time the power of the motor must be increased as follows
A microscope is focused on a mark on a piece of paper and then a slab of glass of thickness $3 \,cm$ and refractive index $1.5$ is placed over the mark. How should the microscope be moved to get the mark in focus again?
A metal wire of linear mass density of 9.8 g/m is stretched with a tension of 10 kg-wt between two rigid supports 1 m apart. The wire passes at its middle point between the poles of a permanent magnet and it vibrates in resonance when carrying an alternating current of frequency n. The frequency n of the alternating source is
A material B? has twice the specific resistance of ?A?. A circular wire made of B? has twice the diameter of a wire made of ?A?. Then for the two wires to have the same resistance, the ratio $l_{B} / l_{A} $ of their respective lengths must be :
A machine is delivering constant power to drive a body along a straight line. What is the relation between the distance travelled by the body against time
A long solenoid has 200 turns per cm and carries a current i. The magnetic field at its centre is 6.28 x$10^{-2}$ 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 liquid does not wet the solid surface if the angle of contact is
A liquid drop of radius $ R $ breaks into $64$ tiny drops each of radius $ r $ . If the surface tension of the liquid is $ T $ , then the gain in energy is
A light spring balance hangs from the hook of the other light spring balance and a block of mass M kg hangs from the former one. Then the true statement about the scale reading is
The physical quantity having the dimensions $\left[ M ^{-1} L ^{-3} T ^{3} A ^{2}\right]$ is
A battery of emf $10\, V$ and internal resistance $3\, \Omega$ is connected to a resistor. The current in the circuit is $0.5\, A$. The terminal voltage of the battery when the circuit is closed is
When a low flying aircraft passes over head, we sometimes notice a slight shaking of the picture on our $TV$ screen. This is due to
A straight wire of mass $200\, g$ and length $1.5\, m$ carries a current of $2\, A$. It is suspended in mid-air by a uniform horizontal magnetic field $B$. The magnitude of $B$ (in tesla) is (assume $g=9.8\, ms ^{-2}$ )
According to classical theory of Rutherford's model, the path of electron will be
An unpolarised beam of intensity $I_{0}$ is incident on a pair of nicols making an angle of $60^{\circ}$ with each other. The intensity of light emerging from the pair is
A diverging meniscus lens of $ 1.5 $ refractive index has concave surfaces of radii $ 3 $ and $ 4\,cm. $ The position of the image, if an object is placed $ 12\,cm $ in front of the lens, is
A converging lens forms a real image $I$ of an object on its principal axis. A rectangular slab of refractive index $\mu$ and thickness $x$ is introduced between $I$ and the lens, $I$ will move
A coin is placed on a horizontal platform which undergoes vertical simple harmonic motion of angular frequency $ \omega $ . The amplitude of oscillation is gradually increased. The coin will leave contact with the platform for the first time
A clock which keeps correct time at $20^{\circ} C$, is subjected to $40^{\circ} C .$ If coefficient of linear expansion of the pendulum is $12 \times 10^{-6} /{ }^{\circ} C$. How much will it gain or lose time ?
A parachutist after bailing out falls $50\, m$ without friction. When parachute opens, it decelearates at $ 2\,m/s^{2} $ . He reaches the ground with a speed of $3 \,m/s$. At what height, did he bail out?
A car, starting from rest, accelerates at the rate $f$ through a distance $S$, then continues at constant speed for time $t$ and then decelerates as the rate $f / 2$ to come to rest. If the total distance travelled is $15 S$, then