the intensity i of light varies inversely as the square of the distance d from the light bulb. suppose l is 640 w/m2 when the distance is 8m. how much farther would it be to point where the intensity is 250w/m2

Answered: the intensity i of light varies…

Algebra: Structure And Method, Book 1

(REV)00th Edition

ISBN:9780395977224

Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole

Publisher:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole

Chapter12: Quadratic Functions

Section12.8: Joint And Combined Variation

Problem 8P

See similar textbooks

Related questions

Concept explainers

Question

the intensity i of light varies inversely as the square of the distance d from the light bulb. suppose l is 640 w/m² when the distance is 8m. how much farther would it be to point where the intensity is 250w/m²

Expert Solution

Given,

The intensity I of light varies inversely as the square of the distance d from the light bulb. That is,

$I α \frac{1}{d^{2}} \Rightarrow I = k \cdot \frac{1}{d^{2}} \to (1), where k is the proportionality constant .$

Given that l is 640 w/m² when the distance is 8m, So put $I = 640 & d = 8$ in equation (1), we get

$\Rightarrow 640 = k \cdot \frac{1}{{(8)}^{2}} \Rightarrow 640 = k \cdot \frac{1}{64} \Rightarrow k = 40960$

Now substituting $k = 40960$ in equation (1), we get

$\Rightarrow I = 40960 \cdot \frac{1}{d^{2}} \Rightarrow I = \frac{40960}{d^{2}}$

Trending now

This is a popular solution!

Step by step

Solved in 2 steps

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

$Linear Equations$

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, algebra and related others by exploring similar questions and additional content below.

Similar questions