A car requires velocity of 36 km /h in 10 sec just after the start . It takes 20 sec to stop . Calculate the acceleration in both the cases
start: a = v/t = 36km/hr/10s = 3.6 km/hr/s
you can convert km/hr to m/s if you desire the usual m/s^2 value.
to stop takes twice as long, so a = 1/2 as much.
Thank you Steve
To calculate the acceleration in both cases, we need to use the formula:
Acceleration = Change in Velocity / Time
Case 1: Car accelerating
Given:
Initial velocity (u) = 0 km/h (as the car just started)
Final velocity (v) = 36 km/h
Time (t) = 10 sec
First, we need to convert the velocities from km/h to m/s to have consistent units:
Initial velocity (u) = 0 km/h = 0 m/s
Final velocity (v) = 36 km/h = (36 * 1000) / 3600 m/s = 10 m/s
Now, we can calculate the acceleration:
Acceleration = (v - u) / t
Acceleration = (10 m/s - 0 m/s) / 10 sec
Acceleration = 10 m/s^2
Therefore, the acceleration of the car when it is accelerating is 10 m/s^2.
Case 2: Car decelerating
Given:
Initial velocity (u) = 36 km/h
Final velocity (v) = 0 km/h
Time (t) = 20 sec
Converting velocities to m/s:
Initial velocity (u) = 36 km/h = (36 * 1000) / 3600 m/s = 10 m/s
Final velocity (v) = 0 km/h = 0 m/s
Now, we can calculate the acceleration:
Acceleration = (v - u) / t
Acceleration = (0 m/s - 10 m/s) / 20 sec
Acceleration = -0.5 m/s^2
The negative sign indicates that the car is decelerating or slowing down.
Therefore, the acceleration of the car when it is decelerating is -0.5 m/s^2.