Question

While walking, why do we press the ground with our feet slightly slanted in the backward direction?

Answer 1

'When we walk, we press the ground in a slightly slanted backward direction, using our feet. Since friction acts in the opposite direction of motion, it pushes us forward. Hence, we are able to walk.'

Friction supplies the support force which is necessary for a body to walk.
Friction is necessary for walking because as per Newton's third law of motion, (every action has an equal and opposite reaction), therefore, we can walk only if the ground we are walking on push our feet back with a force.As per the third law, the ground would definitely push our feet back.
Hope this helps,
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