Physics 1 Midterm Questions & Answers

Physics 1 Midterm Questions & Answers A 50-N crate sits on a horizontal floor where the coefficient of static friction between the crate and the floor is 0.50. A 20-N force is applied to the crate acting to the right. What is the resulting static friction force acting on the crate? A) 20 N to the right. B) 20 N to the left. C) 25 N to the left. D) 25 N to the right. E) None of the above; the crate starts to move. - ANSWER: B) 20 N to the left. A 75-N box rests on a perfectly smooth horizontal surface. The minimum force need to start the box moving is A) 75 N B) 7.5 N C) 750 N D) any horizontal force greater than zero - ANSWER: D) any horizontal force greater than zero A ball is dropped from the top of a tall building. At the same instant, a second ball is thrown upward from the ground level. When the two balls pass one another, one on the way up, the other on the way down, compare the magnitudes of their acceleration: A) The acceleration of the dropped ball is greater. B) The acceleration of the ball thrown upward is greater C) The acceleration of both balls is the same D) The acceleration changes during the motion, so you cannot predict the exact value when the two balls pass each other E) The accelerations are in opposite directions - ANSWER: C) The acceleration of both balls is the same A ball is thrown straight up. At what point does the ball have the most energy? Ignore air resistance