List of top Physics Questions

When an oscillator completes $100$ oscillations its amplitude reduced to $ \frac{1}{3} $ of initial value. What will be its amplitude, when it completes $200$ oscillations?
What is the cause of ''Green house effect'' :-
A rod of length is 3 m and its mass acting per unit length is directly proportional to distance x from one of its end then its centre of gravity from that end will be at :-

A mass is suspended separately by two different springs in successive order then time periods is \(t_1\) and \(t_2\) respectively. If it is connected by both spring as shown in figure then time period is \(t_0\), the correct relation is

A capacitor of capacitance $ C_{1} $ is charged to a potential $V$ and then connected in parallel to an uncharged capacitor of capacitance $ C_{2} $ .The final potential difference across each capacitor will be
The velocity of electromagnetic wave is parallel to :-
Displacement between maximum potential energy position and maximum kinetic energy postion for a particle executing simple harmonic motion is
A disc is rotating with angular speed $\omega$. If a child sits on it, what is conserved :-
For a cell terminal potential difference is 2.2 V when circuit is open and reduces to 1.8 V when cell is connected to a resistance of $R = 5\, \Omega$. Determine internal resistance of cell (r) is then :-
A and B are two conductors carrying a current I in the same direction, $x$ and $y$ are two electron beams moving in the same direction.
A superconductor exhibits perfect
A convex lens is made up of three different materials as shown in the figure. For a point object placed on its axis, the number of images formed are

The velocity of the electromagnetic waves is parallel to : 

To convert a galvanometer into a voltmeter one should connect a : -
The SI unit of radioactivity is
The variation of the intensity of magnetisation (I) with respect to the magnetising field (H) in a diamagnetic substance is described by the graph
In nuclear fission the percentage of mass converted into energy is about
Surface tension of liquid is $5\,N/m$. If a thin film of area $0.02 \,m^2$ is made in a ring then the surface energy will be :
An object is placed 12 cm to the left of a converging lens of focal length 8 cm. Another converging lens of 6 cm focal length is placed at a distance of 30 cm to the right of the first lens. The second lens will produce
A ray of light travels from an optically denser to a rarer medium. The critical angle for the two media is C. The maximum possible deviation of the ray will be
A Carnot's engine is made to work between $200^\circ \,C$ and $0^\circ \,C$ first and then between $0^\circ \,C$ and $-200^\circ \,C$. The ratio of efficiencies of the engine is the two cases is
In a sample of radioactive material, what percentage of the initial number of active nuclei will decay during one mean life ?
The resultant of two forces, one double the other in magnitude, is perpendicular to the smaller of the two forces. The angle between the two forces is
A cell supplies a current of 0.9 A through a $2\,\Omega$ resistor and a current of 0.3 A through a $7\,\Omega$ resistor. The internal resistance of the cell is
$64$ small drops of mercury, each of radius $r$ and charge $q$ coalesce to form a big drop. The ratio of the surface density of charge of each small drop with that of the big drop is