List of top Physics Questions

$T$ is the time period of simple pendulum on the earth's surface Its time period becomes $x T$ when taken to a height $R$ (equal to earth's radius) above the earth's surface Then, the value of $x$ will be:

A Carnot engine with efficiency $50 \%$ takes heat from a source at $600 \,K$ In order to increase the efficiency to $70 \%$, keeping the temperature of sink same, the new temperature of the source will be :

An object of mass $8 kg$ is hanging from one end of a uniform rod CD of mass $2 kg$ and length $1 m$ pivoted at its end $C$ on a vertical wall as shown in figure It is supported by a cable $AB$ such that the system is in equilibrium The tension in the cable is : (Take $g =10 m / s ^2$ )

Bob P is released from the position of rest at the moment shown. If it collides elastically with an identical bob Q hanging freely then velocity of Q, just after collision is (g = 10 m/s²).

In Young's double slit experiment, two slits $S_1$ and $S_2$ are ' $d$ ' distance apart and the separation from slits to screen is $D$ (as shown in figure) Now if two transparent slabs of equal thickness $0.1 \,mm$ but refractive index $1.51$ and $1.55$ are introduced in the path of beam $(\lambda=4000 \mathring {A})$ from $S_1$ and $S_2$ respectively, The central bright fringe spot will shift by ______ number of fringes

A thin uniform rod of length $2 m$, cross sectional area ' $A$ ' and density ' $d$ ' is rotated about an axis passing through the centre and perpendicular to its length with angular velocity $\omega$ If value of $\omega$ in terms of its rotational kinetic energy $E$ is $\sqrt{\frac{\alpha Ad }{ Ad }}$ then value of $\alpha$ is _____ .

In an experiment for estimating the value of focal length of converging mirror, image of an object placed at $40\, cm$ from the pole of the mirror is formed at distance $120 \,cm$ from the pole of the mirror These distances are measured with a modified scale in which there are $20$ small divisions in $1 \,cm$ The value of error in measurement of focal length of the mirror is $\frac{1}{ K } cm$ The value of $K$ is _____

A point source of light is placed at the centre of curvature of a hemispherical surface The source emits a power of $24\, W$ The radius of curvature of hemisphere is $10\, cm$ and the inner surface is completely reflecting The force on the hemisphere due to the light falling on it is ______ $\times 10^{-8} N$

In the following circuit, the magnitude of current $I _1$, is ______ A

Match Column-I with Column-II : Choose the correct answer from the options given below:

Column-I (x-t graphs) Column-II (v-t graphs)

If the gravitational field in the space is given as $\left(-\frac{K}{r^2}\right)$ Taking the reference point to be at $r =2\, cm$ with gravitational potential $V =10 \,J / kg$ Find the gravitational potential at $r =3\, cm$ in SI unit (Given, that $K =6 \,Jcm / kg$)

A sinusoidal carrier voltage is amplitude modulated The resultant amplitude modulated wave has maximum and minimum amplitude of $120 \, V$ and $80\, V$ respectively The amplitude of each sideband is:

Position-time graph for a particle is parabolic and is as shown:

Choose the corresponding v – t graph.

Heat is given to an ideal gas in an isothermal process
A Internal energy of the gas will decrease
B Internal energy of the gas will increase
C Internal energy of the gas will not change
D The gas will do positive work E The gas will do negative work
Choose the correct answer from the options given below:

In the circuit shown, the energy stored in the capacitor is $ n \, \mu \text{J} $. The value of $ n $ is:

Two light waves of wavelengths 800 and $600 nm$ are used in Young's double slit experiment to obtain interference fringes on a screen placed $7 m$ away from plane of slits If the two slits are separated by $0.35 mm$, then shortest distance from the central bright maximum to the point where the bright fringes of the two wavelength coincide will be ___$mm$

For the given circuit, in the steady state, $\left| V _{ B ^{-}}- V _{ D }\right|=$___$V$

Two parallel plate capacitors $C_1$ and $C_2$ each having capacitance of $10 \mu F$ are individually charged by a $100 V D C$ source Capacitor $C_1$ is kept connected to the source and a dielectric slab is inserted between it plates Capacitor $C_2$ is disconnected from the source and then a dielectric slab is inserted in it Afterwards the capacitor $C_1$ is also disconnected from the source and the two capacitors are finally connected in parallel combination The common potential of the combination will be ___$V$
(Assuming Dielectric constant $=10$ )

If a wire of resistance R is connected across Vo, then power is Po. The wire is cut into two equal parts and connected with Vo individually, then the sum of power dissipated is P1, then $\frac{Po}{Pi}$ is $\frac{1}{x}$. Find the value of x.

From the given transfer characteristic of a transistor in CE configuration, the value of power gain of this configuration is 10^x, for R_B = 10 kΩ, and R_c = 1 kΩ. The value of x is_____.

When a resistance of 5Ω is shunted with a moving coil galvanometer, it shows a full scale deflection for a current of 250 mA, however when 1050Ω resistance is connected with it in series, it gives full scale deflection for 25 volt. The resistance of galvanometer is _____Ω .

A particle is performing $SHM$ having position $x$ = $A\; cos\; 30°$, and $A\; = 40 \;cm$. If its kinetic energy at this position is $200 \;J$, the value of force constant in $(kN/m)$ is?

A series $LCR$ circuit consists of $R =80 \Omega, X _{ L }=100 \Omega$, and $X _{ C }=40 \Omega$. The input voltage is 2500 $\cos (100 \pi t ) V$. The amplitude of current, in the circuit, is ___$A$

A solid sphere is rolling on a horizontal plane without slipping. If the ratio of angular momentum about axis of rotation of the sphere to the total energy of moving sphere is π : 22 then, the value of its angular speed will be ______ rad/s.

The displacement equations of two interfering waves are given by
$y_1=10 \sin \left(\omega t+\frac{\pi}{3}\right)$ cm ,
$y_2=5[\sin \omega t+\sqrt{3} \cos \omega t]$ cm respectively.
The amplitude of the resultant wave is ___ cm