ASTR 1P01 Lecture Notes - Lecture 10: Orbital Period, Inverse-Square Law, Gravitational Constant

• School: Brock University
• Department: Astronomy
• Course: ASTR 1P01
• Professor: Bozidar Mitrovic

Document Summary

Astronauts dropped a hammer and feather and the gravitational pull on the. Moon is 6x smaller than on the earth. Indeed, the two objects were always at the same height and accelerating at the same rate thus hit ground at same time: speed changes at the same rate and thus objects fall at the same rate. The ne(cid:449)to(cid:374)"s se(cid:272)o(cid:374)d la(cid:449) i(cid:373)plies that the for(cid:272)e of gra(cid:448)it(cid:455) fg o(cid:374) a (cid:271)od(cid:455) of (cid:373)ass (cid:862)m(cid:863) (cid:374)ear the surface of the earth is given by: Hence, the force of gravity on a body is proportional to its mass. The bigger the mass the larger the force of gravity. Moreover, galileo knew that the distance by which an object has fallen in a given time does not depend on its horizontal speed: they drop at the same rate regardless of horizontal motion, at any given moment. An experiment not carried out in practice but in principle.