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F is inversely proportional to the square of r. When F = 50, r = 3. Calculate the value of F when r= 12. ​

User Nebiros
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1 Answer

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Sure, let's solve this step by step.

If F is inversely proportional to the square of r, it means we can write the relationship as:

F * r^2 = k

where k is a constant. This constant k remains the same for every pair of F and r in our problem due to the property of inverse proportionality.

1. Calculating the Constant:
Let's substitute F = 50, and r = 3 into the above equation to get the constant k. So:

50 * 3^2 = k
50 * 9 = k
450 = k

So we get the constant k as 450.

2. Finding the New F
We know that F2 * (r2)^2 = k. We know the value of k, and r2 is given as 12. Let's substitute these into the equation to find F2 as follows:

F2 * 12^2 = 450
F2 * 144 = 450
F2 = 450 / 144

So, F2 = 3.125

Hence, the value of F when r is 12 is 3.125.

User Ford Prefect
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