Question

The speed of a car increases from 20 km / h to 50 km / h in 10 s. What will be the acceleration of that car?​

Answer 1

Answer:

1.1 m/s²

Explanation:

Given:

Initial velocity, u = 20 km/h = 20 * 1000/3600 = 20 * 5 / 18 = 50/9 m /s

Final Velocity, v = 50 km/h = 50 * 1000/3600 = 50 * 5 / 18 = 125/9 m/s

Time, t = 10 s

We know that acceleration, a = (v-u)/t

$\implies a  = \dfrac{\dfrac{125}{9} - \dfrac{25}{9}}{10}\\\\\\\\\implies a  = \dfrac{\dfrac{125 - 25}{9}}{10}\\\\\\\\\implies a = \dfrac{100}{9} \div 10\\\\\\\implies a = \dfrac{100}{9} \times \dfrac{1}{10}\\\\\\\\\implies \boxed{a = \dfrac{10}{9} = 1.1 ms^{-2}}$