Question

why does it happen the fruits can easily be cut with a sharp knife

Answer 1

Fruits could be cut with the sharp knife easily as knife is the very sharp edge.

So fruits can be cut easily using the sharp edge and it is much more efficient on cutting in the slices for the fruits.

Fruits are soft so that they lack the structural strength and they could be cut easily by knife.

Answer 2

Can easily be cut with a sharp knife because fruits are soft and they lack structural strength. When you use a sharp knife to cut a fruit it doesn't create any resistant as the blade is very sharp but when you cut it with a blunt knife the blade creates a resistant to cut without more pressure on fruits.