# A bus decreases its speed from 80 kilometers per hour to 60 km per hour in 5 seconds, find the acceleration of the bus.

**Speed **is defined as the rate at which an object covers a **distance.**

Acceleration is the rate of change of velocity.

## Answer: The acceleration of the bus is -1.12m/s^{2}

Let us understand the relationship between acceleration, speed and time.

**Explanation:**

**Acceleration a = (V - U) / t**

Given: Initial velocity (U) = 80 km/hr = 80 × 5/18 = 400/18 = 22.2 m/sec

Final velocity (V) = 60 km/hr = 60 × 5/18 = 300/18 = 16.6 m/sec

Acceleration a = (V - U) / t

= (16.6 - 22.2)/5

= -5.6/5

= -1.12 m/s^{2}

Negative sign indicates that the velocity is decreasing.