Question

A particle starts from rest and has an acceleration of $2m/s^2$ for $10sec$. After that, it travels for $30sec$ with constant speed and then undergoes a retardation of $4m/s^2$ and comes back to rest. The total distance covered by the particle is

• A. $650m$
• B. $700m$
• C. $750m$
• D. $800m$

Answer 1

The correct option is C $750m$

$v=20m/s$

For region III,$t=\frac{20}{4}=5$sec

Distance covered is equal the area under velocity time graph

$\frac{1}{2}\times 10\times 20+30\times 20+\frac{1}{2}\times 5\times 20$

$s=750m$