Answer:
Days are longer in the summertime and shorter in the wintertime because of the tilt of the Earth's axis. The Earth's axis is tilted at an angle of about 23.5 degrees relative to its orbit around the sun. This tilt causes different parts of the Earth to receive different amounts of sunlight throughout the year. During the summer, the northern hemisphere is tilted towards the sun, causing the days to be longer. During the winter, the northern hemisphere is tilted away from the sun, causing the days to be shorter. This is why the northern hemisphere experiences summer when the south experiences winter and vice versa.