A newly discovered asteroid of the Aten family is found to be 50% closer to the Sun than the Earth is. Given this, how much sunlight does it receive compared to the Earth?
A) half as much
B) four times as much
C) twice as much
D) about the same

Question

Quizplus · Accepted Answer

The intensity of sunlight decreases as distance from the Sun increases, and the inverse square law tells us that the intensity of sunlight is inversely proportional to the square of the distance from the Sun. Since this asteroid is 50% closer to the Sun than the Earth, it receives 1 / (1.5^2) = 0.44 times as much sunlight as the Earth. This means that it receives about 2.27 times (1 / 0.44) the amount of sunlight as the Earth, which is approximately four times as much.

A Newly Discovered Asteroid of the Aten Family Is Found