In order to make vehicles more energy efficient, what can be done?

A900 kg roller coaster car is travelling westward on the track and begins to slow down from 18m/s to 2m/s. how long does it take the roller coaster car to decelerate if the force acting on the car to slow it is 7024n? how far does the roller coaster travel during this time?

Achild throws a ball with an initial speed of 8.00 m/s at an angle of 40.0° above the horizontal. the ball leaves her hand 1.00 m above the ground. how long is the ball in flight before it hits the ground?

Power can be defined as a. the distance over which work was done. b. how much work can be done in a given time. c. all the work in an given area. d. the energy required to do work.