(English Medium) ICSE Class 10 - CISCE Question Bank Solutions for Physics

What is the cause of refraction of light when it passes from one medium to another?

A light ray suffers reflection and refraction at the boundary in passing from air to water. Draw a neat labelled ray diagram to show it. 

A ray of light passes from medium 1 to medium 2. Which of the following quantities of the refracted ray will differ from that of the incident ray: Speed, intensity, frequency, wavelength? 

Explain the term mechanical advantage.

Define the term velocity ratio.

Define the term efficiency of a machine.

When does a machine act as (a) a force multiplier, (b) a speed multiplier? Can a machine act as a force multiplier and a speed multiplier simultaneously?

1. State the relationship between mechanical advantage, velocity ratio and efficiency.
2. Name the term that will not change for a machine of a given design.

How is the mechanical advantage related with the velocity ratio for an actual machine? State whether the efficiency of such a machine is equal to 1, less than 1 or more than 1.

Draw diagrams to illustrate the position of fulcrum load and effort, in the following:

A seesaw

Draw a diagram to illustrate the position of fulcrum load and effort, in the following:

A common balance

Draw a diagram to illustrate the position of fulcrum load and effort, in the following:

A nut cracker

Draw a diagram to illustrate the position of fulcrum load and effort, in the following:

Forceps

Figure below shows a wheel barrow of mass 15 kgf carrying a load of 30 kgf with its centre of gravity at A. The points B and C are the centre of wheel and tip of the handle such that the horizontal distance AB = 20 cm and AC = 40 cm.

Find:

1. the load arm,
2. the effort arm,
3. the mechanical advantage and
4. the minimum effort required to keep the leg just off the ground.

A fire tongs has arms 20 cm long. It is used to lift a coal of weight 1.5 kgf by applying an effort at a distance 15 cm from the fulcrum. Find:

1. the mechanical advantage of fire tongs and
2. the effort needed.

Classify the following amongst contact and non-contact forces.
normal reaction force,

Classify the following amongst contact and non-contact forces.
Frictional force

Classify the following amongst contact and non-contact forces.
gravitation force

Classify the following amongst contact and non-contact forces.
electrostatic force

Classify the following amongst contact and non-contact forces.
magnetic force