universal law of gravitation

acceleration

(final velocity-initial velocity)/change in time

displacement

(initial velocity)(change in time)+1/2(acceleration)(change in time)2

mass of Earth

5.97e24 kg

radius of Earth

6.37e6 m

universal gravitation constant

6.67e-11 Nm2/kg2

acceleration due to gravity on Earth

9.8 m/s2

Law of Universal Gravitation

All objects in the universe attract each other through gravitational force.

gravitational force formula

F = G (m1m2)/d2

Cavendish

calculated G using Newton's Law

average velocity

displacement/change in time

Galileo

thought all objects fall at the same time if there is no air resistance

Newton

thought gravity is a force acting directly between objects

Einstein

thought gravity is the result of the presence of mass

Aristotle

thought the heavier the mass, the faster an object falls