How Much Light Intensity Is Needed to Suspend a Sheet of Paper?

In summary, the conversation involves determining the light intensity needed to horizontally suspend an 8.5 by 11 inch sheet of black paper in a vertical beam of light that matches its dimensions. Using the equation F=IA/c, the light intensity is calculated to be 4.87x10^7 W/m^2, assuming a force of 9.8x10^-3 N and an area of 6.03x10^-2 m^2. However, there is a concern that this intensity may cause the paper to burn up.
  • #1
lunus
8
0

Homework Statement


For a science project, you would like to horizontally suspend an 8.5 by 11 inch sheet of black paper in a vertical beam of light whose dimensions exactly match the paper.

If the mass of the sheet is 1.0 g, what light intensity will you need?

Homework Equations



Equation I used: F = IA/c


The Attempt at a Solution



F = 9.8x10^-3 N
A = 6.03 m^2
c = 3.00x10^8 m/s^2

I = Fc/A

I = 4.87x10^7 W/m^2

This is my attempt at the solution. I think its correct but I would like to double check. I would appreciate any help. thank you
 
Physics news on Phys.org
  • #2
lunus said:

Homework Statement


For a science project, you would like to horizontally suspend an 8.5 by 11 inch sheet of black paper in a vertical beam of light whose dimensions exactly match the paper.

If the mass of the sheet is 1.0 g, what light intensity will you need?

Homework Equations



Equation I used: F = IA/c


The Attempt at a Solution



F = 9.8x10^-3 N
A = 6.03 m^2
c = 3.00x10^8 m/s^2

I = Fc/A

I = 4.87x10^7 W/m^2

This is my attempt at the solution. I think its correct but I would like to double check. I would appreciate any help. thank you

What's the area of that sheet of paper?
 
  • #3
A = 6.03x10^-2 m^2

The area i had above was a typo
 
  • #4
lunus said:
A = 6.03x10^-2 m^2

The area i had above was a typo

OK, no problem then.

Except that maybe it will burn up?
 

FAQ: How Much Light Intensity Is Needed to Suspend a Sheet of Paper?

What is light intensity?

Light intensity refers to the amount of light energy per unit time and area. It is a measure of the brightness of light and is often measured in units of watts per square meter (W/m²).

What factors affect light intensity?

The intensity of light can be affected by various factors such as the distance from the light source, the angle at which the light hits a surface, and the type of material the light is passing through.

How does light intensity affect plant growth?

Light intensity plays a crucial role in plant growth as it is required for photosynthesis, the process by which plants convert light energy into chemical energy. Insufficient light intensity can lead to stunted growth and weak plants, while too much light intensity can cause damage to plants.

How is light intensity measured?

Light intensity can be measured using a device called a light meter. This device measures the amount of light energy in a given area and converts it into a numerical value, usually in units of lux or foot-candles.

What are some common sources of light intensity?

Natural sources of light intensity include the sun, stars, and fire. Artificial sources include light bulbs, LED lights, and fluorescent lights. Light intensity can also be found in various forms of technology, such as computer screens, phones, and TVs.

Back
Top