On June 21st, when the sun is overhead at the Tropic of Cancer,places in the Northern Hemisphere experience

On June 21st, when the sun is directly overhead at the Tropic of Cancer, places in the Northern Hemisphere experience a longer day and a shorter night. This is because the sun's rays are falling more directly on the Northern Hemisphere, causing the day to be longer and the night to be shorter. This is also known as the summer solstice, and it marks the beginning of summer in the Northern Hemisphere. As the Earth rotates on its axis, different parts of the planet receive different amounts of sunlight, which creates different seasons and lengths of days and nights.