What are the two factors that determine light falls on surface of earth?

The two factors that determine how much light falls on a given area of the Earth's surface are:

Distance from the Sun: The closer a location is to the Sun, the more light it will receive. This is because the Sun's rays are spread out over a smaller area, resulting in a higher concentration of light. For example, the tropics receive more direct sunlight than the polar regions, which are farther from the Sun.

Tilt of the Earth's axis: The tilt of the Earth's axis causes different parts of the planet to receive different amounts of sunlight at different times of the year. This is because the Earth's axis is tilted towards the Sun during the summer months, allowing the northern hemisphere to receive more direct sunlight. Conversely, during the winter months, the Earth's axis is tilted away from the Sun, causing the southern hemisphere to receive more direct sunlight.