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Light

Give one use each of a concave and a convex mirror.

04/11/2024

Science

7th

Light

State two differences between a convex and a concave lens.

04/11/2024

Science

7th

Light

What is a virtual image? Give one situation where a virtual image is
formed.

04/11/2024

Science

7th

Light

Find out the letters of English alphabet or any other language known to
you in which the image formed in a plane mirror appears exactly like
the letter itself. Discuss your findings.

04/11/2024

Science

7th

Light

State the characteristics of the image formed by a plane mirror.

04/11/2024

Science

7th

Light

Match the items given in Column I with one or more items of Column II.
Column I Column II
(a) A plane mirror (i) Used as a magnifying glass.
(b) A convex mirror (ii) Can form image of objects
spread over a large area.
(c) A convex lens (iii) Used by dentists to see
enlarged image of teeth.
(d) A concave mirror (iv) The image is always inverted
and magnified.
(e) A concave lens (v) The image is erect and of the
same size as the object.
(vi) The image is erect and smaller
in size than the object.

04/11/2024

Science

7th

Light

Mark ‘T’ if the statement is true and ‘F’ if it is false:
(a) We can obtain an enlarged and erect image by a convex mirror. (T/F)
(b) A concave lens always form a virtual image. (T/F)
(c) We can obtain a real, enlarged and inverted image by a concave
mirror. (T/F)
(d) A real image cannot be obtained on a screen. (T/F)
(e) A concave mirror always form a real image. (T/F)

04/11/2024

Science

7th

Light

Fill in the blanks:
(a) An image that cannot be obtained on a screen is called
____________.
(b) Image formed by a convex __________ is always virtual and smaller
in size.
(c) An image formed by a __________ mirror is always of the same size
as that of the object.
(d) An image which can be obtained on a screen is called a _________
image.
(e) An image formed by a concave ___________ cannot be obtained on
a screen.

04/11/2024

Science

7th

Electric current and it’s effect

Make four electromagnets with 20, 40, 60 and 80 turns. Connect them
one by one to a battery of 2 cells. Bring the electromagnet near a box of
pins. Count the number of pins attracted by it. Compare the strengths
of the Explain…

04/11/2024

Science

7th

Electric current and it’s effect

An electrician is carrying out some repairs in your house. He wants to
replace a fuse by a piece of wire. Would you agree? Give reasons for
your response.

04/11/2024

Science

7th