Explore topic-wise InterviewSolutions in Current Affairs.

Can we use transformer to step up DC voltage? Explain.

A body falls from a height 'h' on a horizontal surface and rebounds. Then it falls again and again rebounds and so on. If the restitution coefficient is $\frac{1}{3}$, the total time taken by the body to come to rest is

If velocity of a particle is $v\left(t\right)=(3t^2-2t+4)\text{m/s}$, the magnitude of average velocity of the particle in $10\text{sec}$ is

The path difference between the two waves $y_1=a_{1}sin(\omega t-\frac{2\pi x}{\lambda })and{y}_2=a_{2}cos(\omega t-\frac{2\pi x}{\lambda }+\varphi )$ is

A uniform semicircular ring having mass $m$ and radius $r$ is hanging at one of its ends freely as shown in the figure. The ring is slightly disturbed so that it oscillates in its own plane. The time period of oscillation of the ring is

The equation of a plane progressive wave is given by

$y=0.025\sin (100t+0.25x)$

Which of the following represents the velocity of the particle of medium through which the sinusoidal wave is propagating?

Three harmonic waves, having equal frequency $f$ and intensity $I_0$, have phase angles $0,\frac{\pi }{4}\text{and}-\frac{\pi }{4}$ respectively. When they are superimposed, the intensity of the resultant wave is close to:

A body of m is moving in a straight line at a constant speed v. Its kinetic energy is k and the magnitude of its momentum is p. Which of the following relations is/are correct?

The strain energy stored in a body of volume $V$ due to shear strain $\varphi$ is (shear modulus is $G$)

A particle moves according to the equation $x=2t^2-5t+6$. Find (i) average velocity in the first $3\text{sec}$ and (ii) velocity at $t=3\text{s}$.

What is happening to the velocity of the ball vertically projected up throughout its journey?

A point object is placed mid-way between two plane mirrors which are $a$ distance apart. The plane mirrors forms an infinite number of images due to multiple reflections. The distance between the $n^{\text{th}}$ order image (i.e $n^{th}$ image in both the mirrors) formed in the two mirrors is

Question 6

Twinkling of stars is due to atmospheric



(a) dispersion of light by water droplets

(b) refraction of light by different layers of varying refractive indices

(c) scattering of light by dust particles

(d) internal reflection of light by clouds

Two waves of equal amplitude A, and equal frequency travel in the same direction in a medium. The amplitude of the resultant wave is

A capillary tube $A$ is dipped in water. Another identical tube $B$ is dipped in a soap - water solution. Which of the following shows the relative nature of the liquid columns in the two tubes?

A uniform chain of mass $M$ and length $L$ has a part $\frac{L}{3}$ hanging over the edge of a table. If the friction between the table and the chain is neglected, the kinetic energy of the chain as it completely falls off the edge of the table is

A ball is projected from ground with speed 10 m/s, then the minimum angle of projection so that the ball lands on the 2nd stair is

A block $Q$ of mass $M$ is placed on a horizontal frctionless surface $AB$ and a body $P$ of mass $m$ is released on its frictionless slope. As $P$ slides by a length $L$ on this slope of inclination $\theta$, the block $Q$ would slide by a distance

What is the difference between ocillatory and periodic motion?

The temperature coefficient of resistance of a conductor varies as $\alpha \left(T\right)=3T^2+2T$. If $R_0$ is resistance at $T=0$ and $R$ be resistance at $T$ then

The system is released from rest with both the springs in unstretched positions. Mass of each block is $1\text{kg}$ and force constant of each spring is $10\text{N/m}$. Extension of horizontal spring in equilibrium is:

Dependence of intensity of gravitational field (E) of earth with distance (r) from centre of earth is correctly represented by

A block of mass $m$ is placed on an inclined plane which is moving with constant velocity $v$ in horizontal direction as shown in figure. Then find out work done in ground frame by the friction in time $t$, if the block is at rest with respect to the inclined plane.

An open pipe vibrating in its fundamental frequency is suddenly closed at one end. As a result, the frequency of the third harmonic of the closed pipe is found to be higher by $100\text{Hz}$. The fundamental frequency of the open pipe is :-

Work done by air when it expands from 50 litres to 150 litres at a constant pressure of 2 atmosphere is

A battery of emf $10\text{V}$ and internal resistance $3\Omega$ is connected to a resistor. If the current in the circuit is $0.5\text{A}$, what is the resistance of the resistor and terminal voltage of the battery when the circuit is closed ?

A particle of mass $2\text{gm}$ and charge $1\mu \text{C}$ is held at rest on a frictionless horizontal surface at a distance of $1\text{m}$ from the fixed charge of $1\text{mC}$. If the particle is released, it will be repelled. The speed of the particle when it is at a distance of $10\text{m}$ from the fixed charge is

Two tall buildings are $40\text{m}$ apart. With what speed must a ball be thrown horizontally from a window $145\text{m}$ above the ground in one building, so that it will enter a window $22.5\text{m}$ from the ground in the other ?