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Consider
a uniform electric field E =
3 × 10³
îN/C. (a) What is the flux of this
field through a square of 10 cm on a side whose plane is parallel to
the yz plane?
(b) What is the flux through the same square if the normal to its
plane makes a 60° angle with the x-axis?

An ideal gas is kept inside a $4\text{L}$ container at a temperature of $300\text{K}$ and a pressure of $6\text{atmospheres}$. If the pressure is held constant while the volume of the gas is doubled, then find out the new temperature of the gas.

An average emf of $20\text{V}$ is induced in an inductor when the current in it is changed from $2.5\text{A}$ in one direction to $1.5\text{A}$ in the opposite direction in $0.1\text{s}.$ Find the self-inductance of the inductor.

Assuming gravitational potential energy ${}^{\prime }{U}^{\prime }$ at ground level to be zero.

All objects are made up of same material.
$U_P=$ gravitational potential energy of solid sphere
$U_Q=$ gravitational potential energy of solid cube
$U_R=$ gravitational potential energy of solid cone
$U_S=$ gravitational potential energy of solid cylinder

A charged particle is projected in magnetic field $\overline{B}=10\hat{k}$ T from origin in X-Y plane. The particle moves in a circle and just touches a line y = 5m at $x=5\sqrt{3}m.$ Then (mass of particle $=5\times {10}^{-5}kg$ and charge $1\mu C$

A solid sphere of mass $M$ and radius $R$ has a spherical cavity of radius $\frac{R}{2}$ such that the centre of cavity is at a distance $\frac{R}{2}$ from the centre of the sphere. A point mass $m$ is placed inside the cavity at a distance $\frac{R}{4}$ from the centre of sphere. The gravitational force on mass $m$ is

If $x=sec\theta -tan\theta ,y=cosec\theta +cot\theta$, then $xy+1=$ _____

The angle of projection, for which the horizontal range and the maximum height of a projectile are equal is

Write two properties of a material suitable for making (a) a permanent magnet, and (b) an electromagnet

There is an electric field in the $+x$-direction. If the work done on moving a charge of $0.2\text{C}$ through a distance of $2\text{m}$ along a line making an angle of ${60}^{\circ }$ with $+x$ axis is $4\text{J}$. The value of $E$ is ?

In the given constraint, if the the surface and the pulley are frictionless and the string is inextensible, then velocity of the block $A$parallel to the smooth surface is

A block of mass $m$ is placed at the bottom of a massless smooth wedge which is placed on a horizontal surface. When we push the wedge with a constant force, the block moves up the wedge. The work done by the external agent when the block has a speed $v$ and has reached the top of the wedge is

A feather is dropped on the moon from a height of $2m$. The acceleration of gravity on the moon is $1.69{\text{m/s}}^2$. Determine the time for the feather to fall to the surface of the moon.

The image
of a small electric bulb fixed on the wall of a room is to be
obtained on the opposite wall 3 m away by means of a large convex
lens. What is the maximum possible focal length of the lens required
for the purpose?

A short bar magnet of moment $4{\text{Am}}^2$ is placed in the magnetic merdian with its south-pole pointing geographic north. The distance between two null points is found to be $20\text{cm}$.



$\left(ii\right)$If the magnet is turned through ${90}^{\circ }$ , the resultant field at the location of the null point will be.

A capillary tube of radius r is dipped in a liquid of density d and surface tension S. If the angle of contact is θ, the pressure difference between the two surfaces in the beaker and the capillary is

A
fighter plane flying horizontally at an altitude of 1.5 km with speed
720 km/h passes directly overhead an anti-aircraft gun. At what angle
from the vertical should the gun be fired for the shell with muzzle
speed 600 m s^–1
to hit the plane? At what minimum altitude should the pilot fly the
plane to avoid being hit? (Take g
= 10 m s^–2).

The log$\lambda$ -log$E$ graph between the de-Broglie wavelength $\lambda$of an electron and its energy will be

Masses of copper wires are in ratio 1:3:5 and lengths of ratio 5:3:1 . Whats the ratio of their electrical resistances ?

A body starting from rest moves along a straight line with a constant acceleration. The variation of speed (v) with time (t) is represented by the graph



विराम से गति प्रारम्भ करने वाला एक पिण्ड किसी सरल रेखा के अनुदिश नियत त्वरण से गति करता है। समय (t) के साथ चाल (v) के परिवर्तन को किस आरेख द्वारा प्रदर्शित किया जाता है?

A pendulum has time period $T$ for small oscillations. An obstacle $P$ is situated below the point of suspension $O$ at a distance $\frac{3l}{4}$. The pendulum is released from rest. Throughout the motion the moving string makes small angle with vertical. Time after which the pendulum returns back to its initial position is

The position of a moving car at time $t$ is given by $f\left(t\right)=a{t}^2+bt+c,t>0,$ where $a,b$ and $c$ are real numbers greater than $1.$ Then the average speed of the car over the time interval $[t_1,t_2]$ is attained at the point:

In the given velocity-time graph, $AB$ shows that the body has:

The photoelectrons emitted from a given cathode on the incidence of a given monochromatic beam of light have

Find the radius of circle in which a central angle of ${90}^{\circ }$ intercepts an arc of length $27.632\text{cm}$ (use $\pi =3.14$)

A stone dropped from a building of height h and it reaches after t seconds on earth. From the same building if two stones are thrown (one upwards and other downwards) with the same velocity u and they reach the earth surface after $t_1$ and$t_2$ seconds respectively, then