Question: A 120 Newton box is at rest on an incline of 35 degrees. The surface of the incline is frictionless and a rope is attached to the box and exerts a force on the box that is 10 degrees above the incline. What is the force exerted by the rope on the box?

Answer: 69.9 N

Question: Two blocks of masses 20 kg and 8 kg are connected together by a light string and rest on a frictionless level surface. Attached to the 8-kg mass is another light string, which a person uses to pull both blocks horizontally. If the two-block system accelerates at 0.5 m/s², what is the tension in the connecting string between the blocks?

Answer: 10 N

Question: Two blocks of masses 20 kg and 8.0 kg are connected together by a light string and rest on a frictionless level surface. Attached to the 8-kg mass is a second light string, which a person uses to pull both blocks horizontally. If the two-block system accelerates at 0.5 m/s², what is the tension in the second string attached to the 8-kg mass?

Answer: 14 N

Question: An elevator weighing 20 000 N is supported by a steel cable. What is the tension in the cable when the elevator is being accelerated upward at a rate of 3.00 m/s²?

Answer: 26 100 N

Question: Find the tension in an elevator cable if the 1 000-kg elevator is descending with an acceleration of 1.8 m/s², downward.

Answer: 8 000 N

Question: Three identical 6.0-kg cubes are placed on a horizontal frictionless surface in contact with one another. The cubes are lined up from left to right and a force is applied to the left side of the left cube causing all three cubes to accelerate to the right at 2.0 m/s². What is the magnitude of the force exerted on the middle cube by the left cube in this case?

Answer: 24 N

Question: A horizontal force of 200 N is applied to a 55-kg cart across a 10-m level surface. If the cart accelerates at 2.0 m/s², then what is the work done by the force of friction as it acts to retard the motion of the cart?

Answer: -900 J

Question: A golf ball hits a wall and bounces back at 3/4 the original speed. What part of the original kinetic energy of the ball did it lose in the collision?

Answer: 7/16

Question: A 1 200-kg automobile moving at 25 m/s has the brakes applied with a deceleration of 8.0 m/s². How far does the car travel before it stops?

Answer: 39 m

Question: A 10.0-kg box starts at rest and slides 3.5 m down a ramp inclined at an angle of 10° with the horizontal. If there is no friction between the ramp surface and crate, what is the velocity of the crate at the bottom of the ramp?

Answer: 3.5 m/s

Question: A hill is 100 m long and makes an angle of 12° with the horizontal. As a 50-kg jogger runs up the hill, how much work does gravity do on the jogger?

Answer: -10 000 J

Question: A 20-N crate starting at rest slides down a rough 5.0-m long ramp, inclined at 25° with the horizontal. 20 J of energy is lost to friction. What will be the speed of the crate at the bottom of the incline?

Answer: 4.7 m/s