# A Typo?

1. Mar 25, 2010

### mettjl03

A Typo?????

1. The problem statement, all variables and given/known data

The question is: Which of the following are units of momentum?
The possible answers are: A. N x m B. kg x s/m C. kg x m^2/s D. J x s/m E. kg x m^2/s^2

2. Relevant equations

3. The attempt at a solution

Is there a typo on this homework question? I thought that the units for momentum were kg x m/s, N x s, or kN x s. Am I wrong about this? Someone please help I think I'm going crazy lol.

2. Mar 25, 2010

### Staff: Mentor

Re: A Typo?????

There's no typo--one of the answers is correct. Check each one carefully.

3. Mar 25, 2010

### willem2

Re: A Typo?????

What is a Joule in N, m, s

4. Mar 25, 2010

### mettjl03

Re: A Typo?????

A joule is a unit. I dont understand what your asking me.

5. Mar 25, 2010

### Staff: Mentor

Re: A Typo?????

A Joule is a unit of what? What other units can be combined to equal a Joule?

Example: A Newton is a unit of Force, but it's equivalent to kg-m/s^2. (Since F = ma.)

6. Mar 25, 2010

### mettjl03

Re: A Typo?????

Well one Joule = 1 N x m... which is 1 kg x m^2/s^2 (i think). So is that the right answer? Im lost

7. Mar 25, 2010

### Staff: Mentor

Re: A Typo?????

Good.
Go through each potential answer in turn and do a similar analysis in terms of kg, m, and s. Then you can compare its units with momentum units.