Explore topic-wise InterviewSolutions in Current Affairs.

If $C$ is the critical angle and $n$ is the refractive index of a denser medium with respect to the rarer medium, $sinC\times n$ is .

The equation of a wave travelling on a string is $y=4sin(4\pi t-\frac{\pi }{16}x)$ if x and y are in centimetres, then velocity of wave is

Laser light of wavelength $630nm$ incident on a pair of slits produces an interference pattern in which the bright fringes are separated by $8.1mm$. A second light produces an interference pattern in which the fringes are separated by $7.2mm$. Then the wavelength of the second light will be

In the given circuit, capacitor $C$ is charged by cell of emf $E$ and reaches a steady state. At $t=0$, switch $S$ is closed and $A$ and $B$ are equal resistances. Now, consider the following statements.


(1) In steady state, rate of heat production in $A$ and $B$ is different.
(2) During charging, more heat is produced in $B$ than in $A$
(3) In steady state, rate of heat production is same in $A$ and $B$
(4) In steady state, energy stored in capacitor is $\frac{1}{8}C{E}^2$,
Which of the above statements are correct?

A $4\text{kg}$ ball tied to the end of a cord of length $1\text{m}$ is swinging in a vertical circle. The maximum speed at which it can swing, if the cord can sustain a maximum tension of $163.6\text{N}$ will be: [Take $g=9.8{\text{m/s}}^2$]

Which of the following is the correct order of increasing size?

The number of electric field lines crossing an area $A$ is $n_1$ when $\overrightarrow{A}||\overrightarrow{E}$, while number of field lines crossing same area is $n_2$ when $\overrightarrow{E}$ makes an angle of ${30}^{\circ }$ with $\overrightarrow{A}$, then

Find the radius of gyration of a rectangular lamina having mass $m$ about an axis passing through C.O.M and perpendicular to the plane of lamina. (Given: $\text{length,}a=4\text{m};\text{breadth,}b=3\text{m})$

An unpolarised beam of intensity $I_0$ is incident on a pair of Nicol prisms making an angle of ${60}^{\circ }$ with each other. The intensity of light emerging from the pair is-

A train moves at a constant speed of 60.0 km/h towards east for 30 min, then in a direction ${30}^{\circ }$ east of due north for 20.0 min, and then west for 45 min. What are the (a) magnitude(in km/min) and (b) angle of its average velocity during this trip?

A body of mass m is thrown upwards at an angle $\theta$ with the horizontal with speed v. While rising up the speed of the mass after t seconds will be

A block of mass $m$ is placed on a surface with a vertical cross section given by $y=\frac{x^3}{6}$. If the coefficient of friction is $0.5$, the maximum height above the ground at which the block can be placed without slipping is

Two satellites are revolving in the same circular orbit round the centre of the earth. They must have the same :

A block of mass $1kg$ is suspended by a string of mass $1kg$ length $1m$ as shown in figure. Find the tension at the lowest point of the string and force exerted by support on the string.

(Take $g=10m/s^2$)

Pure Si at $300K$ has equal electron and hole concentration of $1.5\times {10}^{16}/m^3$. Doping by indium increases $n_h$ to $4.5\times {10}^{22}/m^3$. What is $n_e$ in doped silicon?

A balloon of mass M is descending at a constant acceleration $\alpha$. When a mass m is released from the balloon, it starts rising with the same acceleration $\alpha$. Assuming that its volume does not change, what is the value of m?

Figure shows a three arm tube in which a liquid is filled upto levels of height $l$. It is now rotated at an angular frequency $\omega$ about an axis passing through arm $B$. The angular frequency $\omega$ at which level of liquid in arm $B$ becomes zero is

Which of the following graphs represent the variation of magnetic field $\left(B\right)$ with distance $\left(R\right)$ from an infinitely long straight conductor?

A solid sphere of mass $M$ and radius $R$ is rolling without slipping as shown in figure. Find out the magnitude of total angular momentum of the sphere about point of contact $\left(P\right)$.

A railway engine whistling at a constant frequency moves with a constant speed. It goes past a stationary observer standing beside the railway track. The frequency (f) of the sound heard by the observer is plotted against time (t). Which of the following best represents the resulting curve?

A near UV photon of 300 nm is absorbed by a gas and then re-emitted as 2 photons. One photon is red with wavelength 760 nm. Hence wavelength of the second photon is:

A particle of mass $m$ is dropped from a height $h$ above the ground. At the same time another particle of the same mass is thrown vertically upwards from the ground with a speed of $\sqrt{2gh}$ . If they collide head-on completely inelastically, the time taken for the combined mass to reach the ground, in units of $\sqrt{\frac{h}{g}}$ is

In YDSE, bichromatic light of wavelengths $400\text{nm}$ and $560\text{nm}$ are used. The distance between the slits is $0.1\text{mm}$ and the distance between the plane of the slits and the screen is $1\text{m}$. The distance of the second region of complete darkness from central maximum is :

1. 3

A charged sphere of radius $0.02\text{m}$ has charge density of $1{\text{Cm}}^{-2}$. The workdone when a charge of $40\text{nC}$ is moved from infinity to a point that is at a distance of $0.04\text{m}$ from the centre of the sphere.

Work done by a force,$F=(-6x^3)\hat{i}N$ , in displacing a particle from x = 4m to x = –2m is: