# Simple problem i need help with

im new to the physics world and know this is probably an easy problem but i dont know where to start

Hold a pencil in front of your eye at a position where its end just blocks out the moon. Make approprite measurements to estimate the diameter of the moon, given that the earth-moon distance is 3.8x10^5km.

i figured that you prob had to measure the end of a pencil which i measured about 1.5 cm which is 1.5x10^-5km but i dont really know what to do from there.

LowlyPion
Homework Helper
im new to the physics world and know this is probably an easy problem but i dont know where to start

Hold a pencil in front of your eye at a position where its end just blocks out the moon. Make approprite measurements to estimate the diameter of the moon, given that the earth-moon distance is 3.8x10^5km.

i figured that you prob had to measure the end of a pencil which i measured about 1.5 cm which is 1.5x10^-5km but i dont really know what to do from there.

How far away was the pencil from your eye?

so use simular triangle theory?

LowlyPion
Homework Helper
so use simular triangle theory?

Yes, that would do it nicely.

Sorry for late reply I guess I missed it last night when I scanned the board.

Good luck.