In a microhematocrit centrifuge, small samples of blood are placed in heparinized capillary tubes. The tubes are rotated at 11 500 revolutions per minute, with the bottoms of the tubes being 9.07 cm from the axis of rotation. Find the circumference of the circle. Find the time of one single rotation. If you divide circumference by the time of rotation, you will find the linear speed of the end of the tubes. Then, calculate the centripetal acceleration.