Question

What forces are applied on us and how can they help us move forward when we are walking?

Answer 1

When we walk, we apply a force F on the earth at an angle θ . Thus, by Newton's third law,

Fme, earth=−Fearth,me

Therefore, the earth exerts a reaction force on us, the horizontal component of which enables us to walk. The force I apply also makes the earth move an extremely tiny bit but not too much because of its gigantic mass.