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, or neither? Explain.

Answer 1

the statements of Sally and Ramón are incomplete for the explanation of the phenomenon needs to unite the two statements.

Step-by-step explanation:

To know if the affirmation of each one is correct it is best to propose the solution of the exercise.

For a body to have an acceleration of the velocity direction there must be a force in the same velocity direction, so acceleration must be

v = v₀ + a t

a = (v - v₀) / t

On the other hand, for a body to be in a circular motion, as velocity is a vector, the change of direction needs a perpendicular acceleration, called a centripetal

`a_(c)` = v² / r

So we see that since the body is accelerating in the curve it must have a tangential acceleration and because it is in the curve it also needs a centripetal acceleration.

Now we can analyze the statements of Sally and Ramón are incomplete for the explanation of the phenomenon needs to unite the two statements.