Question

A toy car of mass $5\text{kg}$ moves up a ramp under the influence of force F plotted against displacement $x$. The maximum height attained is given by

Consider $g=10{\text{ms}}^{-2}$ and $F$ ceases to act as the car reaches $x=11\text{m}$

• A. $y_{max}=20\text{m}$
• B. $y_{max}=15\text{m}$
• C. $y_{max}=11\text{m}$
• D. $y_{max}=5\text{m}$

Answer 1

The correct option is C $y_{max}=11\text{m}$

Work done = Gain in potential energy
Hence the area under the F-x curve gives the gain in the potential energy
Area under curve = mgh
$\Rightarrow \frac{1}{2}\times 11\times 100=5\times 10\times h\Rightarrow h=11\text{m}$