OCR M4 2011 June — Question 1

Exam BoardOCR
ModuleM4 (Mechanics 4)
Year2011
SessionJune
TopicCircular Motion 1

1 When the power is turned off, a fan disk inside a jet engine slows down with constant angular deceleration \(0.8 \mathrm { rad } \mathrm { s } ^ { - 2 }\).
  1. Find the time taken for the angular speed to decrease from \(950 \mathrm { rad } \mathrm { s } ^ { - 1 }\) to \(750 \mathrm { rad } \mathrm { s } ^ { - 1 }\).
  2. Find the angle through which the disk turns as the angular speed decreases from \(220 \mathrm { rad } \mathrm { s } ^ { - 1 }\) to \(200 \mathrm { rad } \mathrm { s } ^ { - 1 }\).
  3. Find the time taken for the disk to make the final 10 revolutions before coming to rest.