Radiation Problem: Find Surface Area of Light Bulb Filament

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In summary, radiation does not directly affect the surface area of a light bulb filament, but it can impact the temperature of the filament which can affect its surface area due to thermal expansion or contraction. Knowing the surface area of a light bulb filament is important for determining its efficiency and lifespan, as a larger surface area allows for more heat dissipation which can affect energy consumption and longevity. The surface area of a light bulb filament can be measured using mathematical formulas or specialized equipment, typically in square meters or square centimeters. The radiation emitted from a light bulb filament is not harmful to humans as it is low energy infrared radiation. The surface area of a light bulb filament does not directly affect its brightness, but it can impact the filament's temperature which can
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Homework Statement


The filament of a light bulb has a temperature of 3.2*10^3°C and radiates 59 watts of power. The emissivity of the filament is 0.38. Find the surface area of the filament.

Homework Equations



[tex]\Delta[/tex]Q/[tex]\Delta[/tex]T=e[tex]\sigma[/tex]AT^4

[tex]\sigma[/tex]=5.67*10^-8

The Attempt at a Solution



59=(.38)(5.67*10^-8)(A)(3.2*10^3)^4

Use needed Algebra to solve for A and I get 2.61e-5, but it's not the right answer.
Can someone please tell me what I am doing wrong?
 
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  • #2
Your temperature 3.2*10^3°C is in Celsius, you need to convert it to Kelvin (K).
 
  • #3
What temperature scale is implied by the Stefan-Boltzmann constant?
 

1. How does radiation affect the surface area of a light bulb filament?

Radiation does not directly affect the surface area of a light bulb filament. However, the intensity of radiation can impact the temperature of the filament, which in turn can affect its surface area due to thermal expansion or contraction.

2. What is the importance of finding the surface area of a light bulb filament?

Knowing the surface area of a light bulb filament is important for determining its efficiency and lifespan. A larger surface area allows for more heat dissipation, which can affect the bulb's energy consumption and longevity.

3. How is the surface area of a light bulb filament measured?

The surface area of a light bulb filament can be measured using mathematical formulas or by performing physical measurements with specialized equipment. It is typically measured in square meters (m²) or square centimeters (cm²).

4. Can radiation from a light bulb filament be harmful?

The radiation emitted from a light bulb filament, also known as thermal radiation, is not harmful to humans. It is in the form of infrared radiation, which is low energy and does not have enough intensity to cause damage to our cells.

5. How does the surface area of a light bulb filament affect its brightness?

The surface area of a light bulb filament does not directly affect its brightness. However, a larger surface area allows for more heat dissipation, which can impact the filament's temperature and in turn affect the brightness of the bulb. Other factors, such as the type of gas inside the bulb and the amount of electric current flowing through the filament, also play a role in determining the bulb's brightness.

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