Answer:
F = 15.625
Explanation:
This question may look quite tricky because of the square number, and fraction, but it is actually quite simple when you break it down.
To calculate this question we need to substitute the number 1000 (because we are told this is f) into where f is in our equation. Our new equation is F=1000/r^2.
Next, we need to substitute the number 8 (because we are told this is r) into where r is in our equation. Our new equation is F=1000/8^2.
At this stage, it is just a matter of putting this information directly into a calculator to find F. The answer we get is 125/8, and to get this is into decimal form, we just divide 8 by 125, and the answer is 15.625. This is our final answer.
I have attached a photograph of this calculation written down.