A monkey pushes a box of mass 25 kg in a straight line across a rough floor. The applied force F has magnitude 85 N and acts downward at an angle 0 = 10° with respect to the horizontal, as shown below. The box is initially at rest at the position x, = 0 m, and it has speed v2 = 0.55 m/s at position x2 = 3 a). Find the coefficient of friction between the box and the floor. b). What is the net work done? c). How much work (magnitude and sign) is done by the friction force?

You are driving through the Ouachita Mountains at 12m/s. You see a maple-leaf oak (Quercus acerifolia) crossing the road and hit the brakes, 20m away. The coefficient of kinetic friction between your tires and the road is μ_k = 0.7. Will you strike this endangered broadleaf? Justify your answer with a calculation.Your final answer should be the distance you will travel before coming to a stop.

Your professor's car has stalled in the middle of the road. He is behind it pushing on the trunk with a force of 20 N forward and downward at an angle 30° relative to horizontal, but the car is not moving. Given that the car has a mass of 980 kg and the coefficient of friction between the car and the road is μ = 0.3, what is the magnitude of the friction force on the car? Select one: OA. 2900 N B. 17 N C. 980 N D. 290 N O E. 25 N

A man wants to move a heavy wooden crate (82 kg) across a wooden floor.  However, since he is taller than the crate, he must pull it using a rope that makes an angle of 42 degrees with the horizontal.  He exerts a force of 312 N as he pulls.  What is the Normal Force exerted by the floor on the crate? What is the size of the Friction Force felt by the crate, if the crate moves at a constant speed in a straight line? Imagine that instead the floor is more slick, so that the crate feels a friction force half of what you calculated above.  What is the crate’s acceleration?

Two crates of fruit  are released from the top of a ramp inclined at 30 degrees from the horizontal and 4.5 meter long. The two crates consist of  an apple crate of mass 20 kg that is placed in front of a watermelon crate of mass 80 kg.  The apple crate has a coefficient of friction of 0.20 while the watermelon crate has a coefficient of friction of 0.15. How long does it take the apple crate to reach the bottom of the incline if it needs to travel a distance of 4.5 meters?

Consider a wooden ramp angled 31.7 degrees above horizontal. If a 20.3-kg wooden block is given a strong shove up the ramp so that it has an initial velocity of 22.9 m/s, how long (in seconds) will it take the block to reach its maximum height (before it starts sliding down)? The coefficient of kinetic friction between the block and the ramp is 0.402.

T2 T1 2 0, crate A supply crate is dropped from an airplane to the survivors of a devastating hurricane. For safety purposes, the crate has two parachutes which deploy from and keep the crate falling at a constant and vertical velocity. The parachutes make upward angles 61 = 35.0° and 62 = 48.0° with the horizontal. If the tension in the parachute making angle 61 is T1 = 142 N, what must the mass of %3D the crate be?

In a movie, a stuntman places himself on the vertical front of a truck as the truck accelerates. The coefficient of static friction between the stuntman and the truck is 0.370. The stuntman is not standing on anything but can “stick” to the front of the truck as long as the truck continues to accelerate. What minimum forward acceleration will keep the stuntman on the front of the truck?

A block is sliding down a ramp at an angle of 0 = 16° to the horizontal. Its initial speed is 2.8 m/s. After sliding 13.6 m along the ramp, it comes to a rest. What is the coefficient of kinetic friction, µ., between the block and the ramp? Ө

A man is driving his car with speed 49.0 mi/h on a horizontal stretch of road. (a) When the road is wet, the coefficient of static friction between the road and the tires is 0.102. Find the minimum stopping distance (in m). m == (b) When the road is dry, H, = 0.598. Find the minimum stopping distance (in m). m