Question

What is the magnitude of the pseudo force on a driver by the racing car he operates, as it accelerates horizontally along a straight line from rest to $60m{s}^{-1}$ in $8.0s$?

(mass of driver $=80kg)$

• A. $0.6kN$
• B. $0.78kN$
• C. $1.4kN$
• D. $1.0kN$

Answer 1

The correct option is A $0.6kN$

Using equations of motion to calculate acceleration and subsequently force :
Initial velocity,

$u=0m{s}^{-1}$
Final velocity,

$v=60m{s}^{-1}$
Time, $t=8s$
Using the equation of motion,

$v=u+at$ (where $a$ is the acceleration)
$\Rightarrow 60=0+8a$

$\Rightarrow a=\frac{60}{8}$

$\Rightarrow a=7.5m{s}^{-2}$

According to the newton's second law-

$F=ma$

$m=80kg$; mass of the driver

$\Rightarrow F=80\times 7.5$

$\Rightarrow F=600N$