Question

A car increases its speed from 20 km/h to 50 km/h in 10 seconds. Its acceleration is

• A. 30 ms${}^{-2}$
• B. 3 ms${}^{-2}$
• C. 18 ms${}^{-2}$
• D. none of these

Answer 1

The correct option is D none of these

acceleration is given by the change in velocity wrt to time.

so the total change in velocity is 30km/s.

acceleration is given by taking care of unit of the time and distance both $\frac{30\times 1000}{10\times 3600}$ $=\frac{1}{12}$ in $m/s$.

so none of the options is correct so the answer is D.