Question

How is centripetal force provided in case of the following?

(i) Motion of planet around the sun,
(ii) Motion of moon around the earth.
(iii) Motion of an electron around the nucleus in an atom.

CLASS - XI PHYSICS (Laws of Motion)

Answer 1

i) in motion of planets around the sun centripetal force is provided by the gravitational force of attraction
ii) in motion of moon around the earth centripetal force is provided by the gravitational force on moon due to the earth.
iii) in motion of electrons around the nucleus in an atom is provided by the electrostatic force.

Answer 2

1. Gravitational force (attractive) between sun and planet.
2. Gravitational force (attractive) between moon and earth.
3. Electrostatic force (attractive) between nucleus and electron.