Pre-Lab for Intensity of Light vs Distance Laboratory Go to the website http://h

Question

Pre-Lab for Intensity of Light vs Distance Laboratory Go to the website http://hyperphysics.phy-astr.asu.edu/hbasevisionisal.html#d to see an illustration that helps explain the inverse square law for light and radiation. Imagine you are an Etsy artist who paints globes with maps of the earth. You have two products, a small globe of radius 3 cm and a large globe of radius 6 cm. With respect to the surface of the sphere, all the continents will have the same relative size to each other or your customers will complain about inaccurate maps. [Question 1] In painting the continents on the two globes, which globe would need more paint to cover South Americal? R-6 cm globe R 3 cm globe R 3 cm globe relative size on each of the spheres, but the total area (with respect to getting enough [Question 2] On which globe does South America cover more area? R- 6 cm globe [Question 3] Explain in your own words what it means that the continents are the same paint to cover the globes) is different. You have a special commission to make the globes transparent (not paint them at all) and to put the 3cm globe inside the 6 cm globe and to put a 4 Watt LED light in the middle of them both for a fancy lamp Intensity of light is proportional to the Power per unit area. Lets say that all 4 watts is output as visible light from the LED. (Wow, you have a 100% efficient LED which is impossible, but let's not quibble about that) The light power shines out and passes through both globes which are perfectly transparent. Let's calculate the Intensity of the light when it reaches the small globe, and when it reaches the large globe. Note that the Area of the globe (surface area) with radius R can be calculated as A 4?R2 then What is the LED Light Power per Area of the small globe? What is the LED Light Power per Area of the large globe? Watts/cm2 Watts/cm2

Explanation / Answer

Q;: 1 b) 6 cm globe

Q 2: r = 6cm globe

The size of all continents are same in both the globes, ut just the area would be different as a globe with large radius will show everything at a larger magnitude, and the magnitude or area of any continent will either increase or decrease with the size of the globe.

Q: 3 SA of globe= 4pi r^2

LED power per area of small globe= 4 watts/ ( 4 pi 3^2) =0.035 watts/cm^2

LED power per area of large globe= 4 watts/ 4 pi 6^2) =0.0088 watts/ cm^2

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.