 |
|---|
| PAGE: 36 | SET: Exercises | PROBLEM: 29 |
Inverse square law :
An object by a light source is inversely proportional to square of the distance from the source.
In the dark room the person is trying to read a book.
Consider the distance between the person and light source is 
.
From the inverse square law 
.
Light is too dim, so the person moves to half distance to the lamp.
Then the distance between the person and the light source is 
.
From the inverse square law,
Find brightness of the light if he moves to half distance to the lamp.
Ratio between 
and 
gives the brightness of the light if he moves to half distance to the lamp.
The light is 
times brighter when the person moves to half distance to the lamp.
The light is 
times brighter when the person moves to half distance to the lamp.
|
"I want to tell you that our students did well on the math exam and showed a marked improvement that, in my estimation, reflected the professional development the faculty received from you. THANK YOU!!!" June Barnett |
|
"Your site is amazing! It helped me get through Algebra." Charles |
|
"My daughter uses it to supplement her Algebra 1 school work. She finds it very helpful." Dan Pease |
Simply chose a support option
  
|