Explore topic-wise InterviewSolutions in .

On a level road, a scooterist applies brakes to slow down from a speed of 10 m/s to 5 m/s. If the mass of the scooterist and the scooter be 150 kg, calculate the work done by the brakes. (Neglect air resistance and friction)

A car is moving with a uniform velocity of 30 m $s^{-1}$. It is stopped in 2 s by applying a force of 1500 N through its brakes. Calculate:

(a) the change in momentum of car,
(b) the retardation produced in car and
(c) the mass of the car.

An elastic isotropic body is subjected to hydrostatic state of stress as shown in the figure. For no change in the volume to occur, what should be its Poisson's ratio?

If there is an explosion on Moon, will it be visible or audible or both on earth? Explain. [3 MARKS]

Two stones lying on the surface of the Earth have mass, a gravitational force will always exist between them and it will try to pull the stones towards each other. But actually, we don’t see the stones moving towards each other, why?

Statement 1: The acceleration because of gravitational force is in the range of ${10}^{-12}$ $m{s}^{-2}$.

Statement 2: Stones are lying on a flat surface, so they cannot move.

Statement 3: The force of friction is much higher than the gravitational force.

Statement 4: The stones are irregular in shape, so they cannot move.

Which statements explains the reason for the above question?

We know that are we are bound the earth because of gravity how do you think the gravitational pull of earth extends

A boy starts from a point $O$ and travels $50m$ in $30s$. He returns back to the same point $O$ in $20s$. Calculate the average velocity of the boy.

Around me I could see random currents of water, splashes of foam and

spray all swirling about.... I left a trail of luminous water and my body glittered like some princess's ball gown.

Therefore phosphorescent means ________________________.

A purse at radius 2.00 m and a wallet at radius 3.00 m travel in uniform circular motion on the floor of a merry-go-round as the ride turns. They are on the same radial line. At one instant, the acceleration of the purse is (2.00 m/ $s^2$)$\hat{i}$ + (4.00 m/ $s^2$)$\hat{j}$ . At that instant and in unit-vector notation, what is the acceleration of the wallet?

नीचे दिए गए वाक्यों में उचित विराम-चिह्न लगाइए −

(क) माँ ने पूछा बच्चों कहाँ जा रहे हो

(ख) घर के बाहर सारा सामान बिखरा पड़ा था

(ग) हाय राम यह क्या हो गया

(घ) रीना सुहेल कविता और शेखर खेल रहे थे

(ङ) सिपाही ने कहा ठहर तुझे अभी मजा चखाता हूँ

A car travels from Bangalore to Mumbai and returns in $20hours$. What is the average velocity and average speed of the car if odometer reading of the car, when it started was $2200km$ and when finished was $3800km$?

What do you mean by average speed?

Compare the gravitational forces exerted by the Sun and the moon on the Earth. (Given: mass of the Sun, $M_s=4\times {10}^{31}$ kg, mass of moon, $M_m=6.3\times {10}^{22}$ kg, distance between the Sun and the Earth, $r=1.3\times {10}^{12}$ m and the distance between moon and the Earth, $r=4.5\times {10}^8$ m).

A body weighs 5 kg in air and 3 kg in water, calculate the upthrust experienced by the body.

Imagine a light planet revolving around a very massive star in a circular orbit of radius R with a period of revolution T. If the gravitational force of attraction between the planet and the star is proportional to $R^{\frac{-5}{2}}$, then

What type of sound waves are produced by a vibrating simple pendulum ?

When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.

What is the charge per unit area in ${\text{C/m}}^2$ of an infinite plane sheet, if the electric field produced by the sheet has magnitude $3\text{N/C}$ ?

(Take ${ϵ}_o=9\times {10}^{-12}{\text{C}}^2/{\text{N-m}}^2$)

Question 4 (b)

How can three resistors of resistances 2 Ω, 3 Ω and 6 Ω be connected to give a total resistance of

(b) 1 $\Omega$ ?

Find the sentences in the text where these words occur:

Look these words up in a dictionary which gives examples of how they are used.

Now answer the following questions.

1. What are the things that can erupt? Use examples to explain the various meanings of erupt. Now do the same for the word surge. What things can surge?

2. What are the meanings of the word trace and which of the meanings is closest to the word in the text?

3. Can you find undistinguished in your dictionary? (If not, look for the word distinguished and say what undistinguished mean.)

Define one coulomb.

A body of mass 1 kg strikes elastically with another body at rest and continues to move in the same direction with one fourth of the initial velocity. What will be the mass of the other body ?

If $q=2t^2+3$, find current at $t=2\text{s}$.

A boy is toppled over while running. Explain why

If the mass of one object is doubled and mass of other remains the same, moreover if distance between them is halved then how does the gravitational force change?