Explore topic-wise InterviewSolutions in Current Affairs.

When a rubber ball is taken to the bottom of a sea of depth $2000\text{m}$, the volume of the rubber ball decreases by $1.5\%$. Find the bulk modulus of the rubber ball.
Take the density of water $\rho =1000{\text{kg/m}}^3$ and $g=10{\text{m/s}}^2$.

A ray of light is incident at angle $i$ on a surface of a prism of small angle $A$ & emerges normally from the opposite surface. If the refractive index of the material of the prism is $\mu$, the angle of incidence $i$ is nearly equal to

The position of the particle is given by $x=3t^2-6t+4$ in $\text{m}$. The acceleration of the particle at $10\text{sec}$ is

A small block is placed on a turn table. The coefficient of static friction between the block and the table is ${\mu }_s=0.5$. If the turn table is rotating with constant angular acceleration $\alpha =3{\text{rad/s}}^2$, what will be the angular speed at which the block begins to slip on the table ?
Given $r=1\text{m},g=10{\text{m/s}}^2.$

A rough horizontal plate rotates with an angular velocity $\omega$ about a fixed vertical axis. A particle of mass $m$ lies on the plate at a distance $\frac{5a}{4}$ from this axis. The coefficient of friction between the plate and the particle is $\frac{1}{3}$. The largest value of ${\omega }^2$ for which the particle will continue to be at rest on the revolving plate is

A spinning top has an angular retardation of $\alpha =k{\omega }^2$ (in ${\text{rad/s}}^2$), where $\omega$ is angular velocity of the top and $k=1{\text{rad}}^{-1}$. At ${\theta }_0=0\text{rad}$, if ${\omega }_0=120\text{rad/s}$, then the relation between angular displacement ($\theta$) and angular velocity is

Distinguish between d.c. and a.c.

A parallel beam of monochromatic light of wavelength $500nm$ is incident normally on a perfectly absorbing surface. The power through any cross-section of the beam is $10W$. What is the force exerted by it?

If velocity of a particle is $v\left(t\right)=2t-4\text{m/s}$, the average speed and magnitude of average velocity of the particle in $5\text{sec}$ respectively are

A body is projected from the ground with an upward velocity of $100\text{m/s}$. The body explodes into two fragments of mass $m$ and $2m$ just after it was projected. If the lighter part comes to rest instantly, find the maximum height attained by the other part.[Take $g=10{\text{m/s}}^2$]

A point object is placed on the principal. axis of a convex lens (f= 15 cm) at a distance of 30 cm from it. A glass plate $(\mu =1.50)$ of thickness 1 cm is placed on the other side of the lens perpendicular to the axis. Locate the image of the point object.

A smooth sphere A is moving on a frictionless horizontal plane with angular speed ω and center of mass velocity v. It collides elastically and head on with an identical sphere B at rest. Neglect friction everywhere. After the collision, their angular speeds are ωA and ωB respectively. Then

A small sphere of density $\rho$ falls from rest into a viscous liquid of density $\sigma$ and viscosity $\eta$. Due to friction, heat is produced. Which of the follwing options correctly represents the relation between the rate of production of heat $H$ and the radius of the sphere $r$ at terminal velocity?

The potential difference between A and B in the following figure is:

A uniform chain of length L and mass M overhangs a horizontal table with its two third part on the table. The friction coefficient between the table and the chain is μ. Find the work done by the friction during the period the chain slips off the table.

If R,C and L denote resistance, capacitance and inductance. Which of the following will NOT have the dimensions of frequency?

A hockey player receives a corner shot at a speed of $15\text{m/s}$ at an angle ${30}^{\circ }$ with $y$ - axis and then kicks the ball along $x$ - axis with speed $30\text{m/s}$. If the mass of the ball is $150\text{gm}$ and it remains in contact with the hockey stick for $0.01\text{s}$, then find the force exerted on the ball along $x$ - axis.

A uniform rod of length $l=100cm$ is bent at its mid-point to make ${90}^{\circ }$ angle. The distance of the centre of mass from the centre of the rod is

Initially a man and a plank of the same mass $m$ are moving on smooth horizontal surface with a velocity $v\text{m/s}$ along positive x-axis. After some time man jumps along negative x-axis with a velocity $v\text{m/s}$ with respect to ground, then the speed of the plank will be

A ball is thrown vertically upwards with a velocity of 20m/s from the top of a multi storey building.The height of the point from where the ball is thrown is 25m from the ground.

(a)How high will the ball rise

(b)How long will it be before the ball hits the ground.

Take g=10m/s

If there is a positivie error of 50% in the measurement of velocity of a body, find the error in the measurement of kinetic energy, given $△$m = 0.

Swaison's Thrush (a fleet of small sized birds of an oscine family), while migrating fly far east across North America before turning south via Florida to reach northern South America. If they do this journey every year taking exactly the same time, to and fro on the same route with the same velocity profile then under which category can we put their motion.

The moment of inertia of a rod of length 'l' about an axis passing through its centre of mass and perpendicular to rod is 'I'. The moment of inertia of hexagonal shape formed by six such rods, about an axis passing through its centre of mass and perpendicular to its plane will be

Assuming that the mass $m$ of the largest stone that can be moved by a flowing river depends upon the velocity $v$ of the water, its density $\rho$ and the acceleration due to gravity $g$. Then $m$ is directly proportional to

Show that the internal energy of the air (treated as an ideal gas) contained in a room remains constant as the temperature changes between day and night. Assume that the atmospheric pressure around remains constant and the air in the room maintains this pressure by communicating with the surrounding through the windows, doors, etc.

A chain of mass $10kg$ and length $8m$ is resting on a rough horizontal surface $(\mu =0.2)$. A force $F=15N$ is applied as shown. Find the length (in $m$) of the chain for which no friction force acts.

Temperature and heat are:

Two thin discs each of mass 4.0 kg and radius 0.4 m are attached as shown in figure to form a rigid body. What is the rotational inertia of this body about an axis perpendicular to the plane of disc $B$ and passing through its center?

A ball of mass 100 g and having a charge of $4.9\times {10}^{-5}C$ is released from rest in a region where a horizontal electric field of $2.0\times {10}^{4}N{C}^{-1}$ exists. (a) Find the resultant forc eacting on the ball. (b) What will be the path of the ball? (c) Where will the ball be at the end of 2 s?

The motion of a particle is described by the equation X = at + bt² , where a= 15cm s^-1 and b =3cm s^-2 . Its instantaneous velocity at t= 3 s will be ______ CM s^-1.

Water and mercury are filled in two identical cylindrical vessels up to the same height. Both vessels have a tiny hole in the wall at the bottom. The velocity of water and mercury coming out of the holes are $v_1$ and $v_2$ respectively. Then:
[Density of mercury $=13.6\text{g/cc}$]

Look at the drawing given in the figure,which has been drawn with ink of uniform line thickness. The mass of ink used to draw each of the two inner circles, and each of the two line segments is $m$. The mass of the ink used to draw the outer circle is $6m$. The coordinates of centres of the different parts are: outer circle ($0,0$), left inner circle ($-a,a$), right inner circle ($a,a$), vertical line ($0,0$), and horizontal line $(0,-a)$. The $y-$ coordinate of centre of mass of the ink in this drawing is:

Charges Q₁ and Q₂ are near each other. We have no information of their position, nature and magnitude, all we know is Q₂ experiences a force of 5N to the right. What can we infer for sure from this?

As shown in the figure, a dust particle with mass $m=5.0\times {10}^{-9}kg$ and charge $q_0=2.0nC$ starts from the rest at point $‘a^{\prime }$ and moves in a straight line to point $b$. What is its speed $v$ at point $b$?

If a black body is heated to a high temperature, it seems to be

If more air is pushed into a soap bubble, the pressure in it?

what is pie in terms of wave?

Uncertainity in position of a hypothetical subatomic particle is $1\AA$ and uncertainty in velocity is $\frac{3.3}{4\pi }\times {10}^{5}m/s$ then the mass of the particle is approximately $[h=6.6\times {10}^{-34}Js]$

The following data is observed in the photoelectric effect experiment when cesium was usedas metal. The threshold frequency of the metal is

Find the number of significant figures in the given data

(p) 0.543 (u) 3

(q) 4.330 (v) 4

(r) $1.32\times {10}^{-2}$ (w) 5

(s) 0.002 (x) 1

Find the derivative of $y\left(x\right)=\frac{x^3}{(x+1{)}^2}$ with respect to $x$.

A body of mass m accelerates uniformly from rest to $v_1$ in time $t_1$. As a function of time t, the instantaneous power delivered to the body is

Show the magnetic field for an isolated electron ignoring earth's effect.