
Jeremy S. answered 12/14/20
Physics Tutor (Experienced and Welcoming)
You can find the centripetal acceleration of an object with the equation ac = v2/r. Here, ac is the centripetal acceleration in m/s2, v is the speed of the object traveling in a circle in m/s, and r is the radius of your circle in meters.
The centrifuge has an angular velocity of 7.5x104 rev/min = 75,000 rev/min. We can use this information to find the speed of a point 7.50 cm from the axis of the centrifuge. After that, we can find the centripetal acceleration.
Speed = Distance/time. Here, our distance is 75,000 circumferences and our time is 1 minute. We can use circumference = 2πr here. Distance = 75,000 x 2πr = 75,000 x 2π x (7.50 cm) = 3,534,000 cm = 35,340 m. The speed is then 35,340 m/min. Speed in m/s = 35,340/60 = 589 m/s.
Now we just plug into ac = v2/r: ac = 5892/0.075 = 4,626,000 m/s2.