Centripetal Force

A "swing" ride at a carnival consists of chairs that are swung in a circle by 12.0 m cables attached to a vertical rotating pole. Suppose the total mass of a chair and its occupant is 220 kg. (a) Determine the tension in the cable attached to the chair. (b) Find the speed of the chair.

Working with vertical circular motion.

A fighter pilot dives his plane toward the ground at 230 m/s. He pulls out of the dive on a vertical circle. What is the minimum radius of the circle, so that the normal force exerted on the pilot by his seat never exceeds three times his weight?

Modern Physics

A rocket is used to place a synchronous satellite in orbit about the earth. What is the speed of the satellite in orbit?

Calculating the work done in a given situation with constant force.

A person removes a 10.5 kg stereo amplifier from a shelf that is 1.82 m high. The amplifier is lowered at a constant speed to a height of 0.75 m. What is the work done by (a) the person (b) the gravitational force that acts on the amplifier

Calculating a star's radial velocity using Ha lines.

The Ha line (Hydrogen) of a certain star is received on Earth at a wavelength of 656 nm. What is the star's radial velocity with respect to the Earth?

Calculating work using tensions and a toboggan during constant force.

A person pulls a toboggan for a distance of 35.0 m along the snow with a rope directed 25 degrees above the snow. The tension in the rope is 94.0 N. A) How much work is done on the toboggan by the tension force? B) How much work is done if the same tension is directed parallel to the snow?

Working with constant force to make the net work equal to 0.

A 1.00 * 10^2 kg crate is being pulled across a horizontal floor by a force P that makes an angle of 30 degrees above the horizontal. The coefficient of kinetic friction is 0.200. What should be the magnitude of P, so that the net work done by it and the kinetic frictional force is zero?

Working with changes in gravitational potential energy.

A 75.0 kg skier rides a 2830 m long lift to the top of a mountain. The lift makes an angle of 14.6 degrees with the horizontal. What is the change in the skier's gravitational potential energy?

Mechanical Energy

A person starts from rest at the top of a large frictionless spherical surface, and slides into the water below. At what angle (theta) does the person leave the surface?

Calculating time using power, mass and displacement.

A 3.00 * 10^2 kg piano is being lifted at a steady speed from ground level straight up to an apartment 10.0 m above the ground. The crane that is doing the lifting produces a steady power of 4.00 * 10^2 W. How much time does it take to lift the piano?