Question

A helicopter is moving at a speed of 56 km/h. One second later it is moving at 58 km/h. What is its acceleration?

• A. 5/9 m/s²
• B. 6 m/s²
• C. 7 m/s²
• D. 5/4 m/s²

Answer 1

The correct option is A

5/9 m/s²

Here, t = 1 s

u= 56 km/h = 56 $\times$ $\frac{5}{18}$ m/s

v= 58 km/h = 58 $\times$ $\frac{5}{18}$ m/s

Using the first equation of motion, v = u + at

or, a = $\frac{v-u}{t}$ = [58 $\times$ $\frac{5}{18}$ - 56 x $\frac{5}{18}$] / 1 = $\frac{5}{9}$ $m/s^2$