Question

If y varies inversely with the square of r, what is the constant of proportionality when y - 10 and 1 = 5?

Answer 1

Question:

If y varies inversely with the square of r, what is the constant of proportionality when y =10 and r = 5?

Answer:

The constant of proportionality is 250

Solution:

Given that,

y varies inversely with the square of r

Which means,

$y \propto \frac{1}{r^2}\\\\y = k \times \frac{1}{r^2}$

Where, "k" is constant of proportionality

Subtitute y = 10 and r = 5

$10 = k \times \frac{1}{5^2}\\\\10 = k \times \frac{1}{25}\\\\k = 10 \times 25\\\\k = 250$

Thus the constant of proportionality is 250