Question

7.11 q: a 1.0 × 10³ - kilogram car travels at a constant speed of 20 me - ters per second around a horizontal circular track. which dia - gram correctly represents the direction of the cars velocity (v) and the direction of the centripetal force (f_c) acting on the car at one particular moment? (1) (2) (3) (4)

Explanation:

Step1: Recall centripetal force and velocity relationship

Centripetal force \(F_{c}\) acts towards the center of the circular path. Velocity \(v\) is tangent to the circular path at any point.

Step2: Analyze each diagram

• Diagram (1): \(F_{c}\) is towards the center and \(v\) is tangent. This is correct.
• Diagram (2): \(F_{c}\) and \(v\) directions are wrong as per the centripetal - velocity relationship.
• Diagram (3): \(F_{c}\) and \(v\) directions are wrong as per the centripetal - velocity relationship.
• Diagram (4): \(F_{c}\) and \(v\) directions are wrong as per the centripetal - velocity relationship.

Answer:

(1)