Chapter 4, Problem 33A

Calculate the acceleration of a bus that goes from 10 km/h to a speed of 50 km/h in 10 seconds.

To determine

Theacceleration of a bus.

Answer to Problem 33A

The acceleration of the bus is $1.1\text{}{\text{m/s}}^2$

Explanation of Solution

Given:

A bus changes its speed from 10 km/hr to 50 km/hr in 10 s.

Formula used:

The final speed, v of an object can be expressed in terms of its initial speed, acceleration, a and time of travel t as,

  $v=u\text{+}at$

For a given change in speed and time, the acceleration can be calculated as,

  $a=\frac{v-u}{t}$

Calculation:

Here, initial speed of the bus is 10 km/hr and final speed is 50 km/hr and the time is 10 s. Thus, the acceleration of the bus is given by,

  $\begin{array}{c}a=\frac{\left(50-10\right)\times \frac{1000}{3600}}{10}\\ \text{=1}{\text{.1 m/s}}^2\end{array}$

Conclusion :

The acceleration of the bus for the given change in speed and time is $\text{1}{\text{.1 m/s}}^2$ .