A 200 ton train is accelerated from rest to a velocity of 30 miles per hour on a level track. How much useful work was done?

What will be the impact on the velocity of an object if it falls with constant acceleration?

If the velocity is positive then which would most likely yield a negative acceleration?

1. An initial velocity that is lower than the final velocity

2. Higher velocity in the middle of the journey

3. An infinite value of time

4. A final velocity that is lower than the initial velocity

What should be the acceleration of a car that can maintain a constant velocity of 50 km/h for 20 seconds?