Question

A car of mass $1000kg$ is moving with a speed of $40m{s}^{-1}$ on a circular path of radius $400m.$ If its speed is increasing at the rate of $3m{s}^{-1}$ the total force acting on the car is :

• A. $3000N$
• B. $4000N$
• C. $5000N$
• D. $7000N$

Answer 1

Answer: (C)

$5000N$

There are two acceleration acting on the body moving in a circular path

The centripetal acceleration is acting towards the radius is given as

$a_c=\frac{v^2}{r}m/s^2$

$a_c=\frac{40\times 40}{400}$

$a_c=4m/s^2$

The tangential acceleration is $3m/s^2$

The resultant acceleration is$\sqrt{3^2+4^2}$

By substituting the values in the above equation we get

We know that the force is given as

$F=ma$

$F=1000\times 5$

Hence the force is $5000N$