Explore topic-wise InterviewSolutions in Current Affairs.

If Linear momentum is defined as 'mass x speed', can we state a principle of conservation of linear momentum as 'linear momentum of a system remains constant if no external force acts on it?

When the numbers of coils get doubled then the self inductance

A man A starts moving east with velocity 6 m/s, another man B starts moving north 30' east with velocity 6m/s. Find velocity of B w. r. t to A

A coin is pushed down tangentially from an angular position $\theta$ on a circular surface, with velocity $v$ as shown. If the cofficient of friction between the coin and surface is $\mu$, find the tangential acceleration of the coin.

The expression $(\frac{1}{\sqrt{2}}\hat{i}+\frac{1}{\sqrt{2}}\hat{j})$ is a

In a concave mirror experiment, an object is placed at a distance $x_1$ from the focus and the image is formed at a distance $x_2$ from the focus. The focal length of the mirror would be

Which is most reactive towards electrophonic reagent?

In a half wave rectifier, the secondary coil S of the transformer is connected to

Light is incident normally on face $AB$ of a prism as shown in figure. A liquid of refractive index $\mu$ is placed on face $AC$ of the prism. The prism is made of glass of refrctive index $3/2$. The limits of $\mu$ for which total internal reflection takes place on face $AC$ is

A box of mass $2\text{kg}$ slides from a height of $8\text{m}$ on the inclined plane and struck the ball. After collision, the ball sticks on the box. If mass of the ball is $200\text{g}$, then what will be the velocity of the box after collision? Assuming all surfaces are frictionless and initially the ball is at rest. (take $g=10m/s^2)$

Evaluate $\int e^x\sin xdx$

A loaded spring gun of mass M fires a shot of mass m with a velocity v at an angle of elevation $\theta$. The gun is initially at rest on a horizontal frictionless surface. After firing, the centre of mass of the gun-shot system

A cubical block is moving on a horizontal smooth plane. It hits a ridge at point $\text{O}$. The angular speed of the block after it hits $\text{O}$ is

Two thin converging lenses are placed on a common axis, so that the center of one of them coincides with the focus of the other. An object is placed at a distance twice the focal length from the left-hand lens. Where will its image be? What is the lateral magnification? The focal length of each lens is $f$.

A non-viscous liquid flows through a horizontal pipe of varying cross-sectional area. Identify the option which correctly represents the variation of height of rise of liquid in each vertical tube.

At the top of the trajectory of a projectile, the directions of its velocity and acceleration are

A uniform rectangular thin sheet ABCD of mass M has length a and breadth b, as shown in the figure. If the shaded portion HBGO is cut - off, the coordinates of the centre of mass of the remaining portion will be

Two Cars $A$ and $B$ are travelling with constant velocities of $10\text{m/s}$ and $20\text{m/s}$ respectively along straight lines making an angle of $60°$ with each other. The magnitude of relative velocity of $A$ with respect to $B$ is

The momentum of a photon in an X-ray beam of ${10}^{-10}$ metre wavelength is

The retarding potential for having zero photo-electron current

A tube closed at one end and containing air is excited. It produces the fundamental note of frequency 512 Hz. If the same tube is open at both the ends the fundamental frequency that can be produced is

[RPET 1999]

The cross product of vectors A = $(\hat{i}+\hat{j})$ and B =$(\hat{i}+\hat{k})$ in

The wave nature of electrons is used in which of the following devices?

A force acts on a 30 gm particle in such a way that the position of the particle as a function of time is given by $x=3t-4t^2+t^3$, where x is in metres and t is in seconds. The work done during the first 4 seconds is

Due to what force a simple pendulum remains in simple harmonic motion?

A simple pendulum performs simple harmonic motion about X = 0 with an amplitude A and time period T. The speed of the pendulum at
$X=\frac{A}{2}$ will be

Complete the following table :

$\begin{array}{ccc}\text{Car Model}& \text{Driver X}& \text{Driver Y}\\ & \text{Reaction time 0.20}& \text{Reaction time 0.30s}\\ \text{A (deceleration on}& \text{Speed = 54 km/h}& \text{Speed = 72 km/h}\\ \text{hard braking}=6.0m/s^2)& \text{Braking distance}a=\cdots \cdots & \text{Braking distance}c=\cdots \cdots \\ & \text{Total stopping distance}& \text{Total stopping distance}\\ & b=\cdots \cdots & d=\cdots \cdots \\ \text{B (deceleration on harsd braking}& \text{Speed = 54 km/h}& \text{Speed = 72 km/h}\\ =7.5m/s^2)& \text{Breaking distance}e=\cdots \cdots & \text{Breaking distance}g=\cdots \cdots \\ & \text{Total stopping distance}& \text{Total stopping distance}\\ & f=\cdots \cdots & h=\cdots \end{array}$

Evaluate: $\int {\sin }^{2}xdx$

Figure shows a small block of mass m which is started with a speed v on the horizontal part of the bigger block of mass M placed on a horizontal floor. The curved part of the surface shown is semicircular. All the surfaces are frictionless. Find the speed of the bigger block when the smaller block reaches the point A of the surface.

The quantum nature of electromagnetic radiation is established beyond doubt by

i) Polarization ii) photoelectric effect

iii) Compton effect iv) Fraunhofer spectrum

Planet $A$ has mass $M$ and radius $R$, planet $B$ has mass $M/3$ and radius $3R$. If escape velocity from planet $A$ is $V_e$, then escape velocity from planet $B$ will be

Stationary waves of frequency 300 Hz are formed in a medium in which the velocity of sound is $1200metre/sec$ . The distance between a node and the neighboring antinode is

If the series limit frequency of the Lyman series is $v_L,$ then the series limit frequency of the Pfund series is

A particle moves in one dimension from rest under the influence of a force that varies with the distance travelled by the particle as shown in the figure. The kinetic energy of the particle after it has travelled $3m$ is

Two light wires A and B shown in the figure are made of the same material and have radii ${\text{r}}_{\text{A}}$ and ${\text{r}}_{\text{B}}$ respectively. The block between them has a mass m. When the force F is $\frac{\text{mg}}{3}$, one of the wires breaks.

The transition from the state n = 3 to n = 1 in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from

If a car covers $\frac{2}{5^{th}}$ of the total distance with $v_1$ speed and $\frac{3}{5^{th}}$ distance with $v_2$ then average speed is

If the speed of the particle is $v=4t^3+6\text{m/s}$, the distance of the particle as a function of time $t$ and the average speed in $3\text{sec}$ respectively are

A horizontal force of $10\text{N}$ is necessary to just hold a block stationary against a wall. The coefficient of friction between the block and the wall is $0.2$. The weight of the block is

Three capacitors are connected to DC source of 10volts shown in the

adjoining figure. If the charge accumulated on plates of C₁,C₂ and C₃ are

respectively, then

The square of the angular velocity $\omega$ of a certain wheel increases linearly with the angular displacement during $100$ revolutions of the wheel’s motion as shown. Compute the time $t$ required for the increment.

The maximum and minimum magnitude of the resultant of two vectors are $23$ units and $7$ units respectively. Then the magnitude of the resultant vector when they act perpendicular to each other is

A light ray is incident on a transparent sphere of index $=\sqrt{2}$ , at an angle of incidence $={45}^{\circ }$. What is the deviation of a tiny fraction of the ray, which enters the sphere, undergoes two internal reflections, and then refracts out into air?