orh.. thanks. =)
Another ques:
Given this formula F=48/x^2, F=force and x=distance,
When the magnets are a certain distance apart, the force is 1.25
newtons. Write down the force when the distance is halved.
We do it in the simple way
When F = 1.25, 1.25 = 48/x²
so x² = 48/1.25
x = 6.197
when distance is halved, x is now 3.098
So, F = 48 / 3.098² = 5 N
Alternatively, a preferred method would be:
When x changes from x to x/2 (halved),
force = 48 / (x/2)²
force = 48 *4 / x²
force = 4F
Since F = 1.25 N originally,
force now = 4 * 1.25 = 5N