You have two similar bars. One is a magnet and the other is a piece of iron. Can you find out whichone of them is a magnet? Explain the process.

-->

Explanation:

I remember being asked something like this a while back so here's what i remember:

tie each rod to a string and hang them. the magnetized bar will face in the North-South direction and the iron bar will rest in a random direction and that's how you know which is which.

Hope that helps.. let me know if you have any follow-ups on this.

gets less

the independent variable, the one that is intentionally manipulated, is whether or not the car hits the barrier.

the dependent variable, the one that you measure the response in, is the distance that the washers travel.