Question

Easy Guided Online Tutorial A special electronic sensor is embedded in the seat of a car that takes riders around a circular loop-the-loop ride at an amusement park. The sensor measures the magnitude of the normal force that the seat exerts on a rider. The loop-the-loop ride is in the vertical plane and its radius is 21 m. Sitting on the seat before the ride starts, a rider is level and stationary, and the electronic sensor reads 770 N. At the top of the loop, the rider is upside down and moving, and the sensor reads 350 N. What is the speed of the rider at the top of the loop?

Answer 1

Answer:

v = 17.30 m / s

Explanation:

For this exercise we will use Newton's second law

at the bottom of the loop and stopped

           ∑ F = 0

           N-W = 0

           N = W

            W = 770 N

the mass of the body is

            W = mg

             m = W / g

            m = 770 / 9.8

            m = 78.6 kg

on top of the loop and moving

           ∑ F = m a

           N + W = m a

note that the three vectors go in the same vertical direction down

           

the centripetal acceleration is

           a = v² / r

we substitute

           N + W = m v² / r

           v = $\sqrt{(N+W) \frac{r}{m} }$

let's calculate

          v = $\sqrt{ (350+770) \frac{21}{78.6} }$

          v = 17.30 m / s