posted by Lee .
1.A race car has a mass of 707 kg. It starts from rest and travels 42.0 m in 3.0 s. The car is uniformly accelerated during the entire time. What net force is exerted on it?
2.A 4430 kg helicopter accelerates upward at 2.2 m/s2. What lift force is exerted by the air on the propellers?
3.A dragster starts with zero velocity and completes a 404.8 m (0.2530 mile) run in 4.915 s. If the car had a constant acceleration, what would be its acceleration and final velocity?
4.Suppose 70 kg boy and a 50 kg girl use a massless rope in a tug-of-war on an icy, resistance-free surface, as in figure 4-21. If the acceleration of the girl toward the boy is 3.0 m/s2, find the magnitude of the acceleration of the boy toward the girl.
5.On Earth, a scale shows that you weigh 645 N.
What is your mass?
What would the scale read on the moon (g = 1.60 m/s2)?