A dime is 1.8 cm in diameter. Earth's moon is 3.844*10¹⁰ cm from Earth and has a diameter of 3.76*10⁸ cm. At what distance from your eye would you have to hold a dime so that it has the same angular diameter as the full moon? A) 200 cm B) 2 cm C) 0.2 cm D) 2 AU E) 2 LY

Question

Quizplus · Accepted Answer

To have the same angular diameter, the ratio of the diameter to the distance must be the same. For the moon, this ratio is 3.76*10^8 cm / 3.844*10^10 cm. For the dime, it should be 1.8 cm / x. Solving for x gives approximately 200 cm.

A Dime Is 1