Question

A motorcycle is going on an over bridge of radius $r$. The driver maintains a constant speed. As the motorcycle is ascending on the over bridge. the normal force on it

• A. increases
• B. decreases
• C. remains the same
• D. fluctuates

Answer 1

The correct option is A increases

$mgcos\theta -N=mv²/r$

$\Rightarrow N=mgcos\theta -mv²/r$

Now, $m,v$ and $r$ will be constant this means they will have the same value throughout the motion. On the other hand, The angle which the line joining the motorcyclist makes with the vertical keeps on deceasing as result cosine value is increasing,

since it increases from $90°$ to $0°$.

As a result, Normal Reaction is increasing continuously.

Hence, the answer is Option $\left(A\right)$