# Creative solution to a physics problem

## Main Question or Discussion Point

This was posted on digg and I don't remember seeing it on here, so i thought I'd share:

:rofl:

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"Does the object continue to move after it comes to a rest?"

.........:rofl:

Kurdt
Staff Emeritus
Gold Member
"Does the object continue to move after it comes to a rest?"

.........:rofl:
Indeed the question is almost as dumb as the answer.

Why?

texttttt

I love it.

Kurdt
Staff Emeritus
Gold Member
Why?

texttttt
It could have been worded better do you not think?

I'm surprised they'd give five points for the second part of that question. It's obvious by inspection. You read the word "frictionless", and the question answers itself.

It could have been worded better do you not think?
Whats wrong with the wording?

Whats wrong with the wording?
Think like a normal person (i.e., one who does not recognize that it only comes to rest for an instant of time). Something that has come to rest has ceased moving. By definition, it will not be moving after it has come to rest.

Interesting aside: the quickest way to reconcile the two perspectives is to point out there is no "after" associated with the rest in question. The time spent at rest is zero.

The question is written the way it is to see who knows the material. If the question said, comes to a rest instantaneously, I think it would be obvious to everyone that its going to move again.

Kurdt
Staff Emeritus
Gold Member
Whats wrong with the wording?
Would you expect five marks for answering no? Evidentally the person who completed the question thought this could be remedied :rofl:

If you put no, you would get a zero. Elephants or not.

Consider this, does this system ever come to a complete rest?

No, it does not. So there can ONLY be one solution implied in the question the way it is written.

LOL.

Qns : What would happen if you connected several light bulbs in a series?

Ans : Nothing, you didn't connect it to a battery.

BobG