Edexcel M4 2017 June — Question 3

Exam BoardEdexcel
ModuleM4 (Mechanics 4)
Year2017
SessionJune
TopicVariable Force

3. A cyclist and her bicycle have a combined mass of 75 kg . The cyclist travels along a straight horizontal road. The cyclist produces a constant driving force of magnitude 150 N . At time \(t\) seconds, the speed of the cyclist is \(v \mathrm {~m} \mathrm {~s} ^ { - 1 }\), where \(v < \sqrt { 50 }\). As the cyclist moves, the total resistance to motion of the cyclist and her bicycle has magnitude \(3 v ^ { 2 }\) newtons. The cyclist starts from rest. At time \(t\) seconds, she has travelled a distance \(x\) metres from her starting point. Find
  1. \(v\) in terms of \(x\),
  2. \(t\) in terms of \(v\).