4. Demarius has just moved, and is unloading boxes the moving van. He slides a 19.0 kg box down the 31. ramp. The box accelerates at a rate of 0.68 m/s2. What is the coefficient of kinetic friction between the box and the ramp?6. Rita places a 2.5 kg block on a frictionless inclined plane that is 30 above horizontal. She applies a horizontal force, which keeps the block from moving up or down the inclined plane. What is the magnitude of the force Rita applies? 1. A 1.95 kg box sits on an incline of 24 with the horizontal. If the box accelerates down the incline at 0.245 m/s, what is the coefficient of kinetic friction between the box and the inclined plane?8. Raquel is moving a 35.4 kg supply bin from classroom to another. To move the bin across the floor at a constant speed, Raquel pushes the bin from above, with a force of 161 N, and at an angle of 17 below horizontal. What is the coefficient of kinetic friction between the bin and floor?2. Carrie pulls a 41.5 kg bin across the floor of her garage using a rope that is attached to the bin. She pulls with a force of 138 N, at an angle of 28.0 above horizontal. The coefficient of kinetic friction between the floor and the box is 0.290. What is the acceleration of the box?5. Alistair places a 6.40 kg block on an inclined plane that is 23" above the horizontal. The block starts from rest, and in 2.20 seconds, travels 1.40 m. What is the force of friction on the block? 3. A 1.45 kg box is placed on a ramp that is 21 above the horizontal. If the coefficient of static friction is 0.49, and the coefficient of kinetic friction is 0.32, what will happen to the box?2. Carrie pulls a 41.5 kg bin across the floor of her garage using a rope that is attached to the bin. She pulls with a force of 138 N, at an angle of 28.0 above horizontal. The coefficient of kinetic friction between the floor and the box is 0.290. What is the acceleration of the box?10. Ginny is snowboarding down a ski slope. Her total mass (including the snowboard) is 68.5 kg. When she reaches the bottom of the slope, she is moving at 6.55 m/s. The coefficient of friction between the snowboard and the ground is 0.088. How fast will Ginny be moving 2 seconds after reaching the bottom of the slope?9. Clarissa accidentally throws her 165 g ying disc onto the roof of her house. The roof is at an angle of 30 above the horizontal. If the disc sits motionless on the roof, what is the force of friction acting on the disc? 7. Kevin works as a janitor, and he is pushing a fully-loaded recycling bin that weighs 557 N across the floor. He applies a force of 410 N at an angle of 15 below the horizontal. The coefficient of kinetic friction between the recycling bin and the floor is 0.46. How long does it take him to move the bin 6.5 meters, assuming the bin starts from rest