- #1

BurpHa

- 44

- 13

- Homework Statement
- A train engine pulls two identical cars behind it. Car 1 is

attached directly to the engine, and car 2 is attached to car 1.

The engine and cars are speeding up. The force of the engine on

car 1 is _____ the force of car 1 on car 2.

A. greater than

B. less than

C. equal to

D. There is no force on either car.

- Relevant Equations
- I would say a relevant law: Newton's third law.

My choice is C, which is "equal to." Here is my reasoning:

The engine pulls on car 1, so car 1 is having a force acting on it, which pulls car 1 forward. Likewise, the same amount of force is applied on car 2 by car 1 by moving forward with the same amount of force from the beginning. So it is reasonable, at least to my intuition, that the force of the engine on car 1 is equal to the force of car 1 on car 2.

However, it turns out that my intuition is wrong. I have reviewed the definition, but I still don't see any flaws in my thinking.

Thank you for your help.

The engine pulls on car 1, so car 1 is having a force acting on it, which pulls car 1 forward. Likewise, the same amount of force is applied on car 2 by car 1 by moving forward with the same amount of force from the beginning. So it is reasonable, at least to my intuition, that the force of the engine on car 1 is equal to the force of car 1 on car 2.

However, it turns out that my intuition is wrong. I have reviewed the definition, but I still don't see any flaws in my thinking.

Thank you for your help.