Question:
A scooter company gives the following specifications about its product.
Weight of the scooter $-95 \mathrm{~kg}$
Maximum speed - $60 \mathrm{~km} / \mathrm{h}$
Maximum engine power - $3.5 \mathrm{hp}$
Pick up time to get the maximum speed $-5 \mathrm{~s}$
Check the validity of these specifications.
Solution:
Max. acceleration,
$a=\frac{v-u}{t}$
$a=(50 / 3-0) / 5=3.33 \mathrm{~m} / \mathrm{s}^{2}$
Force
$\mathrm{F}=\mathrm{ma}=95 \times 3.33$
$F=316.6 \mathrm{~N}$
Velocity
$\mathrm{v}=\frac{\stackrel{P}{F}}{F}=(3.5 \times 746) / 316.6$
$\mathrm{v}=8.2 \mathrm{~m} / \mathrm{s}$