Question

A car when passes through a convex bridge exerts a force on it which is equal to.

• A. $Mg+\frac{M{v}^2}{r}$
• B. $\frac{M{v}^2}{r}$
• C. $Mg-\frac{M{v}^2}{r}$
• D. None of these

Answer 1

The correct option is C $Mg-\frac{M{v}^2}{r}$

Let us suppose that the body exerts a force $N$ on the surface when it travels through the convex surface.

The forces on the car is $mg$ downwards and $N$ upwards.

Hence the total force $mg-N$ will provide the essential centripital acceleration to the car.

Hence $mg-N=\frac{m{v}^2}{R}$

Hence $N=mg-\frac{m{v}^2}{R}$