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Question
State two differences between a convex and a concave lens.
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Solution 1
| Convex lens | Concave lens | |
| 1. | A convex lens can form both real and virtual images | A concave lens always forms a virtual image |
| 2. | It can form a magnified image. | The image is always diminished in size. |
Solution 2
1) A convex lens is thicker in the middle, while a concave lens is thinner in the middle.

2) A convex lens converges the light ray falling on it, while a concave lens diverges the light ray falling on it.

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