A car is coasting backwards down a hill at -3.0 m/s when the driver gets the engine started. After 2.5s, the car is moving uphill at a velocity of +4.5 m/s. What is the car's acceleration?

 

Asked by vijayparmar555115 | 1st May, 2020, 03:03: PM

Expert Answer:

Given :
u = - 3 m/s
v = +4.5 m/s
t = 2.5 s 
a=?
 
According to first equation of motion,
v=u +at 
 
Thus,
 
4.5 =(-3) + a(2.5)
 
4.5 +3 = a(2.5)
7.5 = a(2.5)
 
a = 7.5/2.5 = 3 m/s2 
 
Thus, car's acceleration is 3 m/s2 .
 

Answered by Shiwani Sawant | 1st May, 2020, 03:21: PM