English Medium कक्षा १० - CBSE Important Questions for Science

An old man cannot see objects closer than 1 m from the eye clearly. Name the defect of vision he is suffering from. How can it be corrected? Draw ray diagram for the (i) defect of vision and also (ii) for its correction.

What eye defect is hypermetropia? Describe with a ray diagram how this defect of vision can be corrected by using an appropriate lens.

What is Hypermetropia (far sightedness)? 

Draw a ray diagram to show how Hypermetropia is defect can be corrected using a lens.

A glass prism is able to produce the spectrum when white light passes through it, but a glass slab doesn’t produce any spectrum. Explain why it is so. 

List two causes of presbyopia. Draw labelled diagram of a lens used for the correction of this defect of vision. 

When do we consider a student sitting in the class to be myopic? List two causes of this defect. Explain using a ray diagram how this defect of eye can be corrected.

Solve the following question:
The near point of the eye of a person is 50 cm. Find the nature and power of the corrective lens required by the person to enable him to see clearly the objects placed at 25 cm from the eye?

What is the cause of the dispersion of white light through a glass prism? Draw a ray diagram to show the path of light when two identical glass prisms are arranged together in an inverted position with respect to each other and a narrow beam of white light is allowed to fall obliquely on one of the faces of the prisms.

A person is unable to see objects distinctly placed within 50 cm from his eyes.

(a) Name the defect of vision the person is suffering from and list its two possible causes.

(b) Draw a ray diagram to show the defect in the above case.

(c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm.

(d) Draw a labeled diagram for the correction of the defect in the above case.

A student has to trace the path of a ray of light through a glass prism. List four precautions he should observe for better results.

The phenomena of light involved in the formation of rainbow are ______.

State reasons for Myopia. With the help of ray diagrams, show the:

1. image formation by a myopic eye, and
2. correction of myopia using an appropriate lens.

A person is unable to see clearly a poster fixed on a distant wall. He however sees it clearly when standing at a distance of about 2 m from the wall.

1. Draw ray diagram to show the formation of image by his eye lens when he is far away from the wall.
2. List two possible reasons of this defect of vision.
3. Draw ray diagram to show the correction of this defect using appropriate lens.

Observe the following diagram and answer questions following it: 

1. Identify the defect of vision shown.
2. List its two causes.
3. Name the type of lens used for the correction of this defect.

List two difference in the characteristic properties of the virtual images formed by the two types of spherical lenses (concave and convex). How are these characteristics of the two lenses use in the correction of the two common defects of vision namely myopia and hypermetropia?

State the colour which bends:

1. The most.
2. The least while passing through a glass prism.

When light enters the atmosphere it strikes extremely fine particles, which deflect the rays of light in all possible directions, This is due to ______.

When a beam of white light passes through a region having very fine dust particles, the colour of light mainly scattered in that region is ______.

Name the phenomenon of light responsible for Tyndall effect. Write an event where this phenomenon can be observed.