Question

answer these...

1) Which lens is used in telescope?
2)some examples of surface tension in everyday life.

Answer 1

Transparent lens used in microscope

Answer 2

Ans. 1) In a reflecting telescope, instead of a convex objective lens, a concave mirror is used to collect parallel rays from the object and form an image at the focal point. Then the convex eyepiece lens is used to magnify this image for the viewer.

Ans. 2) Examples of surface tension

## Walking on water: Small insects such as the water strider can walk on water because their weight is not enough to penetrate the surface.

## Floating a needle: A carefully placed small needle can be made to float on the surface of water even though it is several times as dense as water.