Question

Ramon and Sally are observing a toy car speed up as it goes around a circular track. Ramon says, "The car's speeding up, so there must be a net force parallel to the track." "I don't think so," replies Sally. "It's moving in a circle, and that requires centripetal acceleration. The net force has to point to the center of the circle."Do you agree with Ramon, Sally, both, or neither. Explain, in detail.

Answer 1

we must agree with Ramon and Sally's two arguments together to explain the movement. (both)

Step-by-step explanation:

This is an interesting argument of the two people, before answering we propose the solution of the problem.

Let's use Newton's second law. Since the car is rotating in a circle there must be a centripetal force towards the center of the circle given by the expression

F = m a = m v² / r

Where v and r are the velocity module and the radius of the circle respectively.

In addition, the car is accelerating whereby the speed module is changing, for this to occur there must be a force in the same direction of movement (tangential) that creates this tangential acceleration to the circle.

From the arguments given there must be two force components: a tangential component that creates the change of the velocity module and a radial component that creates the change in the velocity direction.

Let's analyze the response of the two people

We see that Ramon's argument explains the tangential acceleration and Sally's argento explain it centripetal acceleration, but neither has the complete explanation, so to have the whole explanation we must take the two arguments together and unite them.

In short, we must agree with Ramon and Sally's two arguments together to explain the movement.