Lenses

Question 1

What is the shale and action of diverging lens on light rays?

Answer 1

Diverging lens have concave shape (thinner in the middle)

They cause incoming light rays to diverge away from each other

Question 2

Define focal length for converging lens

Answer 2

The focal length is the distance between its optical Centre and principal focus

Question 3

Define linear magnification for a converging lens

Answer 3

Height of image/Height of object = image distance/object distance (v/u)

Question 4

What is the lens formula?

Answer 4

1/f= 1/u + 1/v

F is focal length, v is image distance and u is object distance

Question 5

What are properties of rays passing through the optical Centre?

Answer 5

They are not deviated

Question 6

What are properties of rays parallel to the principal axis?

Answer 6

They will be refracted to pass through the focal point on the other side of the lens

Question 7

What are the properties of rays parallel to each other?

Answer 7

They will converge to a point on the focal plane

Question 8

What is the shape and action of a converging lens on light rays?

Answer 8

Converging lenses are convex (thicker in the middle)

They cause incoming light rays to converge at a single point