But have local inequities in forces
At center of Earth, moon’s gravitational attraction balances exactly the centripetal acceleration for Earth’s circular path
Elsewhere on Earth, gravitational attraction need not balance centripetal acceleration exactly
- Because all points on Earth trace out circles of equal radii, all points experience equal centripetal acceleration
- Gravitational attraction exerted by moon diminishes with increasing distance according to the inverse square law
If gravitational & centripetal accelerations have different magnitudes at different points, forces cannot be equal