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Question
A box with a weight of 50 N rests on a horizontal surface. A person pulls horizontally on it with a force of 15 N and it does not move. To start it moving, a second person pulls vertically upward on the box. If the coefficient of static friction is 0.4, what is the smallest vertical force for which the box moves?
A) 5 N
B) 12 N
C) 20 N
D) 25 N
E) 35 N
Answer
This answer is hidden. It contains 1 characters.
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