# Where am I going wrong with this problem?

1. Feb 9, 2007

### Canadian

The four 1.0 g spheres shown in the figure are released simultaneously and allowed to move away from each other.

Here's my attempt at a solution. All sphere's have same charge and are situated in a square.

Thanks.

2. Feb 9, 2007

### Staff: Mentor

I'm assuming you are asked for the final velocity of each of the masses with respect to the stationary frame of reference. One error I see, 1g does not equal 0.0001kg. The rest of your approach looks reasonable.

3. Feb 9, 2007

### Canadian

Thanks, corrected the mass (silly me) and recalculated. Computer still doesn't like this answer???

Any ideas?

4. Feb 9, 2007

### Staff: Mentor

I'm getting a different exponent on the potential energy terms. Maybe check your units in each of the equations to be sure you are using mks throughout. (Of course I may be calculating the potential energies wrong as well.)

5. Feb 10, 2007

### Canadian

My goodness it is questions like these that make me so angry. Just got an email back from my Prof he said I need to think about all the pairs in the problem. So I needed to take into account all six pairs in the problem (1 on 2, 1 on 3, 1 on 4, 2 on 3, 2 on 4, and 3 on 4).

Got the answer correct now thanks for all your help.

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