In uniform circular motion, Select one: a. the velocity always points towards the center of the circle. Ob. the acceleration always points away from the center of the circle. O c. the acceleration and the velocity are always perpendicular. d. there is no fixed relationship between the direction of the acceleration and the direction of the velocity. e. the acceleration and the velocity are always parallel.

# 16. The frequency of a merry go round is 5 times per minute. What is the tangential velocity of the merry go round if it has a radius of 20.0 meters? a. 3.00 m/s b. .050 m/s c. 10.5 m/s d. 6.28 m/s #17. The frequency of a merry go round is 5 times per minute, and it has a radius of 20.0 meters. What is the angular velocity of the merry go round in degrees per second? a. 18.0 degrees/s b. .050 degrees/s c. 30.0 degrees/s d. 60.0 degrees/s

If the earth revolves around the sun at a constant distance of 1.50 x 1011 m, what is the centripetal acceleration of the sun if one earth year is 365 days?   a. 4.0 x 10-3 m/s2   b. 3.0 x 10-3 m/s2   c. 6.0 x 10-3 m/s2   d. 5.0 x 10-3 m/s2   e. 2.0 x 10-3 m/s2

A search and rescue helicopter travels at constant speed in a horizontal plane. The figure below shows a portion of the path traveled by the helicopter, as viewed looking down from above. The helicopter's path includes three straight portions between points "1" and "2", points "4" and "5", and points "7" and "8", each of which has a length of 4000 m, as shown in the figure. It takes the helicopter 2000 seconds to travel along each of these straight portions of its path. The semi-circular portions of the path (also shown in the figure) have the same radius R=500m. +y YNorth) 8. 4 4000 m A semi-circle is one half of a circle. East 6.