Question

The figure below shows the velocity-time graph for the motion of a bike. Find the displacement of the bike in time interval $EF$.

• A. $45m$
• B. $35m$
• C. $25m$
• D. $55m$

Answer 1

The correct option is B $35m$

Displacement of the bike in time interval $EF$ = Area under $BC$.
Area under $BC$ = Area of trapezium $EBCF$
$\therefore$ Area of trapezium $EBCF$ $=\frac{1}{2}(EB+FC)\times \left(EF\right)$
$\Rightarrow$ $\frac{1}{2}(25+10)\times (5-3)$ = $\frac{1}{2}\left(35\right)\left(2\right)$
$\Rightarrow$ $35m$
Hence, the displacement of the bike in time interval $EF$ is $35m$.