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Galileo_Galilei
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Homework Statement
A woman is standing on a flat section of ground. Her weight is 500N. Newton's third law states that there must be an equal an equal and opposite force to her weight, which is
A. The Earth exerting an upward force of 500 N on the woman.
B. The woman exerting an upward force of 500 N on the earth
C. the woman exerting a downward force of 500 N on the earth
D. the Earth exerting a downward force of 500 N on the woman
Homework Equations
Well, the fact that every force has an equal and opposite force acting on it
The Attempt at a Solution
C and D are obviously nonsense.
I would automatically have gone for 'A', but the answer in the book begs to differ, saying the answer is 'B' .
I always thought the Earth exerts an equal and opposite force on all the things sitting on it.
So how can a woman exert an upward force of 500 N on the earth?