(English Medium) ICSE Class 9 - CISCE Question Bank Solutions for Physics

Calculate the mass of a body whose volume is 2m³ and relative density is 0.52.

A piece of metal weighs 44.5 gf in air, 39.5 gf in water. What is the R.D. of the metal?

A body of volume 100 cm³ weighs 1 kgf in air. Calculate its weight in water. What is its relative density?

An aeroplane is moving uniformly at a constant height under the action of two forces (i) Upward force (lift) and (ii) Downward force (weight). What is the net force on the aeroplane?

A tennis ball and a cricket ball , both are stationary. To start motion in them .

Define linear momentum and state its S.I. unit.

A body of mass m moving with a velocity v is acted upon by a force. Write an expression for change in momentum in each of the following cases: (i) When v << c, (ii) When v → c and (iii) When v << c but m does not remain constant. Here, c is the speed of light.

Show that the rate of change of momentum = mass × acceleration. Under what condition does this relation hold?

Two bodies A and B of same mass are moving with velocities v and 2v, respectively. Compare their (i) inertia and (ii) momentum.

Two balls A and B of masses m and 2 m are in motion with velocities 2v and v, respectively. Compare:

(i) Their inertia.

(ii) Their momentum.

(iii)  The force needed to stop them in the same time.

State the Newton's second law of motion. What information do you get from it?

Write the mathematical form of Newton's second law of motion. State the conditions if any.

State Newton's second law of motion. Under what condition does it take the form F = ma?

How can Newton's first law of motion be obtained from the second law of motion?

Use Newton's second law of motion to explain the following instance : 

A cricketer pulls his hands back while catching a fast moving cricket ball .

Use Newton's second law of motion to explain the following instance :
An athlete prefers to land on sand instead of hard floor while taking a high jump .

The correct form of Newton's second law is : 

The unit of linear momentum is :

The linear momentum of a body of mass m moving with velocity v is  : 

A body of mass 5 kg is moving with velocity 2 m s^-1. Calculate its linear momentum.