Dr. H’s Reality Check: An On-Ramp with a Slope

We are going to calculate how long a sloped on-ramp needs to be. A 1500 kg Dodge Neon can accelerate from 0-60mph (0-27m/s) in 7 seconds on level ground. This implies the car can produce a 5700N force in the forward direction. An on-ramp is being built at an angle of 10 degrees with respect to the horizontal. How long does it need to be, so this car can reach a speed of 65 mph.

Reality Check

Suggested:

Questions: 5, 9, 15, 17, 22,

Handout on the back

Problems: 3, 10, 26, 29, 38, 66

Answers

4. 1260 N

10. 1290N

32. 320 N, 0.98 m/s²

38. 103 N, 0 N

66. 21000 N, 1.1 m

2. Bob sits on the chair to the left and Mary sits on the chair to the right. Both chairs are on frictionless rollers. Bob and Mary face each other then push each other away. Bob has a larger mass than Mary. Draw a Free Body Diagram for each. Which experiences the larger force? Which has a larger acceleration. Explain why.

Mary