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A circular-motion addict of mass 70.0 kg rides a Ferris wheel around in a vertical circle of radius 12.0 m at a constant speed of 5.0 m/s. What is the magnitude of the normal force on the addict from the seat when both go through the highest point of the circular path?

A person pushes a 41.5kg block of ice  at an angle 25.80 below the horizon across a lake as shown in the figure.   Calculate the minimum force F (in N) he must exert to get the block moving. (Hint: Horizontal component of force = Static friction force) (The coefficient of static friction is 0.1 and the coefficient of kinetic friction is 0.03)

A  spring stretches 3.52 cm vertically when a 1.50 kg object is suspended from it.  Find the distance (in cm) the spring stretches if you replace the 1.50 kg object with a 2.40 kg object. Assume that the spring obeys the Hook’s law.

A circular-motion addict of mass 60.0 kg rides a Ferris wheel around in a vertical circle of radius 12.0 m at a constant speed of 6.0 m/s. What is the magnitude of the normal force on the addict from the seat when both go through the highest point of the circular path?

A 5.20 g bullet moving at 609 m/s strikes a 810 g wooden block at rest on a frictionless surface. The bullet emerges, traveling in the same direction with its speed reduced to 485 m/s. What is the resulting speed of the block?

How fast must a 1.7-g ping-pong ball move (in m/s) in order to have the same kinetic energy as a 138.5 g baseball moving at 26.5 m/s?

A shopper pushes a grocery cart 36.0 m at constant speed on level ground, against a 46.0 N frictional force. He pushes in a direction 38.0° below the horizontal. What is the work (in J) done on the cart by the shopper?

The only force acting on a 3.1 kg canister that is moving in an xy plane has a magnitude of 4.6 N. The canister initially has a velocity of 2.3 m/s in the positive x direction, and some time later has a velocity of 4.7 m/s in the positive y direction. How much work is done on the canister by the 4.6 N force during this time?

In the figure, a frictionless roller coaster car of mass m = 848 kg tops the first hill with speed v0 = 15.0 m/s at height h = 43.0 m. What is the speed of the car at  point B.

A 135.5-kg wood block is resting on a wooden floor, what maximum force (in N) can you exert horizontally on the block without moving it? ( Coefficient of static friction between crate and wood floor is 0.5)