Why do strawberries have seeds on the outside?

Coz seeds feel hot inside.

No.

First of all, a fruit is formed from a flower.

A flower consists of ovary, ovule, petals, sepals, stamens, etc.

Most of these parts are attached to receptacle.

Now, usually after fertilization, the ovule forms a seed and the ovary swells to form a fruit.

Whereas, the remaining parts of the flower fall off.

Now, a strawberry flower has multiple ovaries.

When fetilization occurs, all the ovaries form fruits but they don't swell.

Instead, the receptacle of the strawberry flower swells to form the red edible part of the strawberry.

The tiny fruits get embedded on the surface of the enlarged receptacle.

While, the remaining parts fall off.

Thus, the seeds on the outside of the strawberry are actually tiny fruits, each of which contains a seed.