A car is coasting backwards downhill at a speed of 3.0 m/s when the driver gets the engine started. After 2.5 s, the car is moving uphill at 4.5 m/s. Assuming that uphill is positive direction, what is the car's average
acceleration.

0.6m/s²

Explanation:

Given parameters:

Initial velocity  = 3m/s

Final velocity  = 4.5m/s

Time taken  = 2.4s

Unknown:

Average acceleration  = ?

Solution:

To solve this problem, we use the expression:

 Acceleration  =  

v is the final velocity

u is the initial velocity

t is the time taken

    Acceleration  =   = 0.6m/s²

at positions a, g kinetic energy is maximum.

at position d, potential energy is maximum.

grav forces affect all objects magnetic forces affect magnetic objects and electric currents