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state two differences between a convex and a conca...

Question:
State two differences between a convex and a concave lens.

Answer:

Difference between concave lens and convex lens are following:

Concave lens	Convex lens
1. This lens is thinner in the centre than at its edges.	1. This lens is thicker at the centre than at its edges.
2. It is called diverging lens.	2. It is called converging lens.
3. The principal focus is virtual.	3. The principal focus is real.
4. The focal length is negative.	4. The focal length is positive.

rays Concave lens

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Question:
State two differences between a convex and a concave lens.

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Question:
State two differences between a convex and a concave lens.