During batting practice, the ballplayer swings his bat with a velocity of 14 m/s. if the bat is 0.65m long, what is the centripetal acceleration at the end of the bat? (ignore the length of the ballplayer's arm)

The astronauts on the space shuttle flights experienced an acceleration of 29 m/s2 (about 3 "g's") during lift-off. what upward force must the astronaut's seat apply to the astronaut in order to cause this acceleration? assume the astronaut's mass is 70 kg, and compute this force when the acceleration is near the earth's surface so their weight equals latex: mg m g .