Jennymae13viz
Answered

a car has an initial velocity of 40 m/s it stops over a distance of 120 m when the brakes are applied. How long does it take for the car to stop? what is the acceleration.

Sagot :

Akahanaairiviz
 40 m/s = V
120 m = T
A=3
Rhyckayenviz
1) Find the acceleration: 
Equation: a= (v2²-v1²) / 2d
where:
a=acceleration
v2=final velocity ( 0 m/s)
v1=initial velocity (40 m/s)
d=distance (120 m)
Solution:
a=(v2²-v1²) / 2d
a=(0²-40²) / 2(120)
a= -1600 / 240
a= -20/3
a= -6.67 m/s²------->answer
2) Find time:
t=v2-v1/ a
t= 0-40 / -6.67
t= -40/-6.67
t = 6 seconds--------->answer