Explore topic-wise InterviewSolutions in Current Affairs.

With what minimum acceleration can a fireman slides down a rope while k breaking strength of the rope is $\frac{2}{3}$ his weight

A conducting rod $\text{PQ}$ of length $l=1.0\text{m}$ is moving with a uniform speed $v=20\text{m/s}$ in a uniform magnetic field $B=4.0\text{T}$ directed into the paper. A capacitor of capacity $C=10\mu \text{F}$ is connected as shown in figure. Then

If $|\overrightarrow{A}\times \overrightarrow{B}|$ = $\sqrt{3}\overrightarrow{A}.\overrightarrow{B}$, then the value of $|\overrightarrow{A}+\overrightarrow{B}|$ is

Match the following:



Table-1
Table-2

A body starts from rest and moves with a constant acceleration. Which one of the following graphs represent the variation of its kinetic energy $K$ with the distance travelled $x$ ?

A wooden plank of length $1\text{m}$ and uniform cross-section is hinged at one end to the bottom of a tank as shown. The tank is filled with water up to a height of $0.5\text{m}$. The specific gravity of the plank is $0.5$. The angle $\theta$ made by the plank in equilibrium position is

The wavelength of a red night lamp that I use in my house (not that I am scared of monsters under my bed, it is just a habit) is 700 nm. Find the energy contained in each photon of light.

A thin circular ring of mass $M$ and radius ${}^{\prime }{r}^{\prime }$ is rotating about its axis with a constant angular velocity $\omega$. Four objects each of mass $m$, are kept gently to the opposite ends of two perpendicular diameters of the ring. The angular velocity of the ring will be

A wave travels on a light string. The equation of the wave is $y=A\sin (kx-\omega t+{30}^{\circ }$). It is reflected from a heavy string tied to the end of the light string at $x=0$. If $64\%$ of the incident energy is reflected, then the equation of the reflected wave is

The earth’s magnetic field (B_E) at the equator is horizontal, uniform and points north – south. A conducting square loop of side l and resistance R is kept in the vertical plane with two of its sides pointing east-west direction. This loop is moved in east direction with a velocity v. The current induced in the loop is

If $\overrightarrow{B}$ makes an angle of ${53}^{\circ }$ and $\overrightarrow{C}$ makes an angle of ${37}^{\circ }$ with $x-$axis as shown in the figure and the magnitude of $\overrightarrow{A}$ and $\overrightarrow{C}$ is equal to $10$ and $5$ respectively, then the magnitude of $\overrightarrow{B}$ is [Given, $\overrightarrow{A}+\overrightarrow{B}+\overrightarrow{C}=0$] (Take $\sqrt{9804}=99)$

A vessel contains $N$ molecules of a gas at temperature $T$. Now the number of molecules is doubled, keeping the total energy in the vessel constant. The temperature of the gas is.

A uniform metallic conducting wire has a resistance of $30\Omega$ and is bent into an isosceles triangle of triangle of sides in the ratio of 4:3:3. Find effective resistance across the ends of the longest side.

An $\alpha -$particle of energy $5\text{MeV}$ is scattered through ${180}^{\circ }$ by gold nucleus. The distance of the closest approach is of the order of -



The atomic number of gold is $79$.

Which of the following input - output relationship is both linear and time - invariant ?

An electron having mass $m$ with an initial velocity $v=v_0\hat{i}$ in an electric field $E=E_0\hat{i}.$ If ${\lambda }_0=\frac{h}{m{v}_0}$, its de-Broglie wave length at time $t$ is given by-

Find the time required for a cylindrical tank of height $H$ and radius $r$ to drain half of the water through a circular hole of the area $a$ at the bottom. The flow-through hole is according to the law $v\left(t\right)=k\sqrt{2gh\left(t\right)}$, where $v\left(t\right)$ and $h\left(t\right)$ is the velocity of flow through hole and height above the hole respectively at the time $t$ and $g$ is the gravitational acceleration.

1. 1215

A block $1$ of mass $0.2\text{kg}$ sliding to the right over a frictionless elevated surface as shown in the image. The speed of block $1$ is $8.00\text{m/s}$. The block undergoes an elastic collision with stationary block $2$, which is attached to a spring of spring constant $1208.5\text{N/m}$. After the collision, block $2$ oscillates in SHM with a period of $0.140\text{s}$, and block $1$ slides off the opposite end of the elevated surface landing at distance $d$ from the base of that surface after falling through height $(h=4.90\text{m})$. What is the value of $d$? [Take $g=9.8{\text{m/s}}^2$]

The mathematical form of three travelling waves are given by

$Y_1=\left(2cm\right)sin(3x-6t)Y_2=\left(3cm\right)sin(4x-12t)and{Y}_3=\left(4cm\right)sin(5x-11t)$

of these waves,

One of the square faces of a metal slab of side $50\text{cm}$ and thickness $20\text{cm}$ is rigidly fixed on a horizontal surface. If a tangential force of $30\text{N}$ is applied to the top face, then the displacement (in $\text{m}$) of the top face is :

[The shear modulus of the material is $4\times {10}^{10}{\text{N/m}}^2$]

Find the
value of the trigonometric function

A source of sound is moving towards a stationary observer with ${\left(\frac{1}{10}\right)}^{th}$ of the speed of sound. The ratio of apparent to real frequency is



[Assume, medium is stationary]

A bike racer starting from rest is riding with constant angular acceleration on a circular track. The ratio of angular displacement of the cyclist during $5^{th}$ and $7^{th}$ second is given by

The potential energy of a molecule on the surface of liquid compared to one inside the liquid is

A long straight metal rod has a cavity of radius $a$ drilled parallel to the axis of the rod as shown in the figure. If the rod carries a current $i$ find the value of magnetic induction on the axis of the hole, [where $\text{OC}=c$]

A three hinged semicircular arch of radius 'R' carries a uniformly distributed load 'w' per unit run over the whole span. The horizontal thrust is

A light of wavelength $\lambda$ is incident on a metal sheet of work function $\varphi =2eV$. The wavelength $\lambda$ varies with time as $\lambda =3000+40t$, where $\lambda$ is in $A^{\circ }$ and t is in second. The power incident on metal sheet is constant at 100 W. This signal is switched on and off for time intervals of 2 minutes and 1 minute respectively. Each time the signal is switched on, the $\lambda$ start from initial value of $3000A^{\circ }$. The metal plate is grounded and electron clouding is negligible. The efficiency of photoemission is 1% $(hc=12400eV{A}^{\circ }).$

The total number of photoelectrons ejected in one hour is ​​​​​​​

The time period of an object performing SHM is $16\text{s}$. It starts its motion from the equilibrium position. After $2\text{s}$ its velocity is $\pi \text{m/s}$. What is its displacement amplitude?

A body moves such that its position varies with time according to $x\left(t\right)=3t^2$. What is its velocity at=3sec?