For passenger comfort the centripetal acceleration on a railway curve must not exceed 2 m/s². What is the smallest radius rmin for a curve taken at 200 km/h?
Circular motion worksheet with answers
A 700 kg car drives around a flat curve of radius 160 m at a constant 19 m/s. Find its centripetal acceleration ac.
A small ball on a string of length 0.6 m moves in a horizontal circle so that the string makes a constant angle of 20° with the vertical (a conical pendulum). Use g = 9.81 m/s². Find the time T for one revolution.
A car takes a flat curve of radius 70 m. The coefficient of static friction between tyres and road is 0.8. Use g = 9.81 m/s². Find the highest speed vmax at which the car can take the curve without skidding.
A 1 kg ball on a string 1.3 m long is swung in a vertical circle. At the lowest point it moves at 7.5 m/s. Use g = 9.81 m/s². Find the tension T in the string at the lowest point.
A small cart is released from rest on a frictionless track and runs into a vertical loop of radius 7 m. From what minimum height hmin above the bottom of the loop must it start to stay on the track at the top of the loop?
Answer key
- 1. rmin = 1543 m
- 2. ac = 2.256 m/s²
- 3. T = 1.506 s
- 4. vmax = 23.44 m/s
- 5. T = 53.08 N
- 6. hmin = 17.5 m
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