A 42.0-kg parachutist is moving straight downward with a speed of 3.85 m/s. (a) If the parachutist comes to rest with constant acceleration over a distance of 0.750 m, what force does the ground exert on her? (b) If the parachutist comes to rest over a shorter distance, is the force exerted by the ground greater than, less than, or the same as in part (a)? Explain.

A string is tied to a 3.2 kg object on a table and a 1.5 kg object hanging over a pulley.The coefficient of kinetic friction between the 3.2 kg object and the table is0.30.(a) Draw FBD for each object. D/(b) Calculate the acceleration of each object.(c) Determine the magnitude of the tension in the string.(d) How far will the objects move in 1.2 s if the initial velocity of the 3.2 kg object is1.3 m/s [right]?

A 60.0 kg crate rests on a level floor in a warehouse. The coefficients of static and kinetic friction are 0.850 and 0.550 respectively. (a) What horizontal pushing force is required to just start the crate to move across the floor? (b) What horizontal pushing force is required to keep the crate moving at a constant velocity across the floor? (c) Include a force (or free-body) diagram of each of the situations.

A 620 kg car pulling a 495 kg trailer accelerates forward at a rate of 2.20 m/s2. Assume frictional forces on the trailer are negligible. Ignore air drag.   (c) What is the force (in N) exerted by the trailer on the car?   Magnitude: Direction: (forward or backward)

An object with a mass of 4kg lies on a rough plane inclined at 20 degrees to horizontal. A force of 35N is applied parallel and up the plane. The object accelerates at 2.5m/s^2. What is the Uk between the object and plane

A large cube (mass = M) being accelerated across a horizontal frictionless surface by a horizontal force . A small cube (mass = m) is in contact with the front surface of the large cube and will slide downward unless is sufficiently large. The coefficient of static friction between the cubes is u. What is the smallest magnitude that F can have in order to keep the small cube from sliding downward?

Block 1 (10 kg) is pulled by a rope from left to right up a ramp which is inclined 50 degrees from the horizontal. The rope pulls on block 1 with a force of 150 N parallel to the surface of the inclined plane. The coefficient of kinetic friction between the block and the surface equals 0.3. Weight force on block 1 by EarthW1E =  i +  j N Tension force on block 1 by RopeT1R =  i +  j N Normal force on block 1 by SurfaceN1S =  i +  j N Frictional force on block 1 by Surfacef1S =  i +  j N What is the acceleration a of block 1?a =  i +  j m/s2