Question

As a roller coaster car crosses the top of a 50-m-diameter loop-the-loop, its apparent weight is the same as its true weight.
What is the car's speed at the top?

Answer 1

Answer:22.36 m/s

Explanation:

Given

the diameter of loop d=50 m

the radius of loop r=25 m

At the top position, we can write,

weight and Normal reaction combination will provide the centripetal force i.e.

$R+W=\frac{mv^2}{r}$

$R=W\quad \quad [\text{apparent weight =Actual weight}]$

$2W=2mg=\frac{mv^2}{r}$

$v=\sqrt{2gr}$

$v=\sqrt{2\times 10\times 25}$

$v=22.36\ m/s$