A bus moving on a straight road at a speed of 10 km/h increases its speed to 70 km/h in 2 minutes. Find its average acceleration.

Solution

To find the average acceleration of the bus, we'll use the formula for acceleration: Acceleration = Change in velocity/ Time taken The change in velocity is the final velocity minus the initial velocity. Given that the initial velocity (vi) is 10 km/h and the final velocity (vf) is 70 km/h, and the time taken is 2 minutes, we first need to convert the time to hours. 2 minutes = 2/60 hours = 1/30 hours Now, we can calculate the change in velocity: Change in velocity = uf- vi = 70 km/h -10 km/h = 60 km/h The time interval (At) over which this change occurs is 2 minutes. Since we typically use Sl units for such calculations (seconds or hours), and since the answers are in km/minute², let's keep the time in minutes for consistency. Thus, At = 2 minutes. Now, we calculate the average acceleration: a=60 km/h 2 minutes =30 km/h per minute To convert this to more standard units, let's express it in terms of km/min²: