Observe the velocity-time graph of a moving car and answer the following questions




a. At what time was the car stopped?
b. At what time did the car have the greatest velocity?
c. What was the greatest velocity?
d. At what time(s) was the car accelerating?
e. Calculate the distance covered by the car in first two hours
f. Calculate the acceleration of the car from ‘E’ to ‘F’
g. How long the car does has zero acceleration?
h. Describe the journey of the car from ‘C’ to ‘D’

Dear student,

(a) car stops when the velociy of car is zero and the velocity of car is zero at t = 6 to t = 7 hours. Therefore, at that time car is stopped.
(b) the car has greatest velocity from point B to D i.e. 80 km/hr ,this velocity remains same at t = 2 to t = 4 hours
(c) the greatest velocity is 80km/hr
(d) The car is accelerating from point A to B, C to D, E to F for 2 hours in each .
Car is accelerating between t=0 to t=2 , t = 4 to t = 6 and t = 7 to t = 9 hours
(e) Distance = velocity * time
                    = 80 / 2 
                    = 40 km in first 2 hours 
(f) Acceleration = V(2) - V(1) / t (2) - t (1)
                         = 60-0/ 9-7
                         = 60 / 2
                         = 30 km/hr
(g) car has zero acceleration when the final and initial velocity are same.
from point B - c , D - E , F- G has same velocity hence zero acceleration
For 4 hours car has zero acceleration.
(h) from point C to D the velocity of car decreases and after 2 hours from point C the car stops having zero velocity.

Regards