1
00:00:00,000 --> 00:00:02,000
Well let's plug into this equation.
2
00:00:02,000 --> 00:00:07,000
When we carry out this multiplication, we get a result of -1.35 x10¹⁰ J.
3
00:00:07,000 --> 00:00:12,000
Now notice that this is a negative number and in fact, if r were smaller,
4
00:00:12,000 --> 00:00:16,000
so these were closer together, it would have been a more negative number.
5
00:00:16,000 --> 00:00:19,000
It would have been a lower potential energy.
6
00:00:19,000 --> 00:00:22,000
Now in genuine physics, objects like to be in a low energy state.
7
00:00:22,000 --> 00:00:27,000
Balls like to roll downhill and positive charges like to be with negative charges.
8
00:00:27,000 --> 00:00:31,000
And we can see in this equation that if one charge is positive and the other negative,
9
00:00:31,000 --> 99:59:59,999
well this energy will be negative, and this r want to be as small as it possibly can.