A cat rides a merry-go-round while turning with uniform circular motion. At time t1 = 2.00 s, the cat's velocity is v1 = (2.50)i + (4.00 m/s)j , measured on a horizontal xy coordinate system. At time t2 = 6.00 s, a half-revolution later, its velocity is v2 = (-2.50 m/s)i + (-4.00 m/s)j .
(a) What is the magnitude of the cat's centripetal acceleration?
(b) What is the magnitude of the cat's average acceleration during the time interval t2 - t1?