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

AI Thread Summary
To suspend an 8.5 by 11 inch sheet of black paper weighing 1.0 g in a vertical beam of light, a light intensity of 4.87x10^7 W/m^2 is calculated. The force acting on the paper is determined to be 9.8x10^-3 N, and the corrected area of the paper is 6.03x10^-2 m^2. There is a concern about the potential for the paper to burn due to the high intensity of light required. The calculations and assumptions made in the solution are being double-checked for accuracy. The discussion emphasizes the need for precise measurements and considerations in the experiment.
lunus
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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
 
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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?
 
A = 6.03x10^-2 m^2

The area i had above was a typo
 
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?
 
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