You are 2.4 from a plane mirror, and you would like to take a picture of yourself in the mirror. you need to manually adjust the focus of the camera by dialing in the distance to what you are photographing. what distance do you dial in?
a. 1.2 m
b. 2.4 m
c. 3.6 m
d. 4.8 m

An athlete swings a ball, connected to the end of a chain, in a horizontal circle. the athlete is able to rotate the ball at the rate of 8.13 rev/s when the length of the chain is 0.600 m. when he increases the length to 0.900 m, he is able to rotate the ball only 6.04 rev/s. (a) which rate of rotation gives the greater speed for the ball? 6.04 rev/s 8.13 rev/s (b) what is the centripetal acceleration of the ball at 8.13 rev/s? m/s2 (c) what is the centripetal acceleration at 6.04 rev/s? m/s2