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Write a general formula to describe the variation. F varies inversely with d^2; f=21 when d=7

Write a general formula to describe the variation. F varies inversely with d^2; f-example-1
User Anemoia
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1 Answer

9 votes
9 votes

Given:

F varies inversely with d²

So,


\begin{gathered} F\propto(1)/(d^2) \\ \\ F=(k)/(d^2) \end{gathered}

Where (k) is the proportionality constant

We will find the value of (k) using the given condition

When F=21, d= 7

Substitute with (F) and (d):


\begin{gathered} 21=(k)/(7^2) \\ k=21\cdot7^2=21\cdot49=1029 \end{gathered}

So, the answer will be:

The general formula to describe the variation is:


F=(1029)/(d^2)

User Kirill Korolev
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3.1k points