why is it hot in the summber and cold in the winter?

Answer 1

North of the equator this is true, south of the equator it reverses (hot in winter, cold in summer).

It is the Earths tilt combined with the distance from the sun as we orbit around it.

Answer 2

Easy.- The primary cause of the seasons is the 23.5 degree of the Earth's rotation axis with respect to the plane of the ecliptic. This means that as the Earth goes around its orbit the Northern hemisphere is at various times oriented more toward and more away from the Sun, and likewise for the Southern hemisphere. Thus, we experience Summer in the Northern Hemisphere when the Earth is on that part of its orbit where the N. Hemisphere is oriented more toward the Sun and therefore the Sun rises higher in the sky and is above the horizon longer, and the rays of the Sun strike the ground more directly. Likewise, in the N. Hemisphere Winter the hemisphere is oriented away from the Sun, the Sun only rises low in the sky, is above the horizon for a shorter period, and the rays of the Sun strike the ground more obliquely. Got it? GOOD.

Answer 3

The 1st guy above is mostly right. The earth's tilt is the reason for the seasons. Distance doesn't matter as much. Otherwise, the seasons would not be opposite on northern and southern hemispheres. In fact, in the upper hemisphere, we are closer to the sun in winter than in summer.

Answer 4

Actually, the distance from the sun has little to do with it. When the weather is hotter the rays from the sun are hitting the earth more directly. When its colder it comes at more of an angle.