m F 0 You are pressing a box against a sloped ceiling, perpendicular to the ceiling itself, as shown in the figure. The mass of the box is m=3.3 kg, the angle of the ceiling is 8=37°, and the coefficients of friction are us=0.31 and μk=0.2. (a) What is the minimum force needed from you to keep the box at rest? N (b) Choosing up the sloping ceiling to be the positive direction, suppose you push with a force 4 N smaller than your answer to the previous part. What will be the acceleration of the box? m/s2

m F 0 You are pressing a box against a sloped ceiling, perpendicular to the ceiling itself, as shown in the figure. The mass of the box is m=3.3 kg, the angle of the ceiling is 8=37°, and the coefficients of friction are us=0.31 and μk=0.2. (a) What is the minimum force needed from you to keep the box at rest? N (b) Choosing up the sloping ceiling to be the positive direction, suppose you push with a force 4 N smaller than your answer to the previous part. What will be the acceleration of the box? m/s2