(a) At what altitude above Earth’s surface will the acceleration due to gravity drop…
PHYSICS · Subjective · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
(a) At what altitude above Earth’s surface will the acceleration due to gravity drop to one-quarter of its surface value? Express your answer both in kilometres and as a percentage of Earth’s radius R.
(b) A high-altitude research balloon is released from rest at this altitude in an evacuated tube (so air resistance is negligible). What is the initial acceleration of the balloon and in which direction does it act? Justify your answer briefly.