Scarlett

Use conservation of energy to determine the angular speed of the spool shown in Figure P8.36 after the 3.00 kg bucket has fallen 4.05 m, starting from rest. The light string attached to the bucket is wrapped around the spool and does not slip as it unwinds.

http://www.webassign.net/sercp/p8-36.gif

please help!

A rotating wheel requires 5.00 s to rotate 30.0 revolutions. Its angular velocity at the end of the 5.00 s interval is 96.0 rad/s. What is the constant angular acceleration of the wheel?

The answer 25 rad/s^2 is within 10% of the correct value.

A skier starts from rest at the top of a hill that is inclined at 12.0° with the horizontal. The hillside is 190.0 m long, and the coefficient of friction between the snow and the skis is 0.0750. At the bottom of the hill, the snow is level and the coefficient of friction is unchanged. How far does the skier move along the horizontal portion of the snow before coming to rest?

answer is in meters

Two blocks, A and B (with mass 50 kg and 100 kg, respectively), are connected by a string, as shown in Figure P5.64. The pulley is frictionless and of negligible mass. The coefficient of kinetic friction between block A and the incline is µk = 0.30. Determine the change in the kinetic energy of block A as it moves from C to D, a distance of 23 m up the incline if the system starts from rest.

picture:

http://www.webassign.net/sf/p5_64.gif

(a) What is the tangential acceleration of a bug on the rim of a 9.0 in. diameter disk if the disk moves from rest to an angular speed of 78 revolutions per minute in 5.0 s?

m/s2

(b) When the disk is at its final speed, what is the tangential velocity of the bug?

m/s

(c) One second after the bug starts from rest, what is its tangential acceleration?

m/s2

What is its centripetal acceleration?

m/s2

What is its total acceleration?

m/s2

° (relative to the tangential acceleration)

If the average speed of an orbiting space shuttle is 18200 mi/h, determine the time required for it to circle the Earth. Make sure you consider the fact that the shuttle is orbiting about 200 mi above the Earth's surface, and assume that the Earth's radius is 3963 miles.

A tennis ball with a speed of 5.0 m/s is thrown perpendicularly at a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 3.0 m/s. If the ball is in contact with the wall for 0.017 s, what is the average acceleration of the ball while it is in contact with the wall? Take the initial direction of motion to be the positive direction. (Indicate the direction of the acceleration by the sign of your answer.)