English Medium Class 9 - CBSE Question Bank Solutions

The volume of a 500 g sealed packet is 350 cm³. Will the packet float or sink in water if the density of water is 1 g cm⁻³? What will be the mass of the water displaced by this packet?

What are the various energy transformations that occur when you are riding a bicycle?

An echo returned in 3 s. What is the distance of the reflecting surface from the source, given that the speed of sound is 342 m s⁻¹?

Does sound follow the same laws of reflection as light does? Explain.

When a sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound production remains the same. Do you hear echo sound on a hotter day?

What name is given to the product of mass and velocity of a body ?

What does the slope of a speed-time graph indicate ?

What can you say about the motion of a body if its speed-time graph is a straight line parallel to the time axis ?

What will be the momentum of a body of mass ‘m’ which is moving with a velocity V ?

What conclusion can you draw about the acceleration of a body from the speed-time graph shown below .

Fill in the following blank with suitable word :

In a speed-time graph, the area enclosed by the speed-time curve and the time axis gives the…………….. by the body.

Name the property of bodies (or objects) to resist a change in their state of rest or of motion.

The mass of object A is 6 kg whereas that of another object B is 34 kg. Which of the two objects, A or B, has more inertia ?

With which physical quantity should the speed of a running bull be multiplied so as to obtain its momentum ?

Fill in the following blank with suitable word :
(a) ………………is a measure of the inertia of a body.

Name the two quantities, the slope of whose graph give acceleration.

A body of mass 25 kg has a momentum of 125 kg.m/s. Calculate the velocity of the body.

Calculate the momentum of the following :
(a) an elephant of mass 2000 kg moving at 5 m/s
(b) a bullet of mass 0.02 kg moving at 400 m/s

Describe the term ‘inertia’ with respect to motion.

On what factor does the inertia of a body depend ? Which has more inertia, a cricket ball or a rubber ball of the same size ?