Fill in the following blanks with suitable words :
A Convex lenses are ______________ in the middle than at the edges whereas concave lenses are _________ in the middle than at the edges.

Answer

To fill in the blanks in the given statement, we need to understand the characteristics of convex and concave lenses.

1. **Understanding Convex Lenses:**
- A convex lens is thicker in the middle than at the edges. This means that the central part of the lens bulges outwards, making it thicker compared to the edges.

2. **Understanding Concave Lenses:**
- A concave lens, on the other hand, is thinner in the middle than at the edges. This means that the central part of the lens curves inward, making it thinner compared to the edges.

Now, we can fill in the blanks:

**Solution:**
A convex lens is **thicker** in the middle than at the edges, whereas a concave lens is **thinner** in the middle than at the edges.

**Final Answer:**
A convex lens are **thicker** in the middle than at the edges whereas concave lenses are **thinner** in the middle than at the edges.

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