Given:
distance from the projector lens to the image, di
projector lens focal length, f
distance from the transparency to the projector lens, do
thin lens equation: 1/f = 1/di + 1/do
do = 4 inches
di = 8 feet
convert feet to inches, for uniformity.
1 foot = 12 inches
8 feet * 12 inches/ft = 96 inches
1/f = 1/96 inches + 1/4 inches
Adding fractions, denominator must be the same.
1/f = (1/96 * 1/1) + (1/4 * 24/24)
1/f = 1/96 + 24/96
1/f = 25/96
to find the value of f, do cross multiplication
1*96 = f * 25
96 = 25f
96/25 = f
3.84 = f
The focal length of the project lens is 3.84 inches
The colors that you see on the CD are created by white light reflecting from ridges in the metal. When light reflects off or passes through something with many small ridges or scratches, you often get rainbow colors and interesting patterns. They are called interference patterns.
Answer:
Comets
Explanation:
The Kuiper Belt is a collection of trans-Neptunian objects that consist of comets and other dwarf planets, including Pluto.
The closer to the equator, the hotter the climate will be.
A prime example of how culture has contributed to human survival is the development of agriculture, which helps feed enormous numbers of people. Option A is correct.
<h3 /><h3>What is culture?</h3>
A population's collective ways of life are known as culture. The manner of life for an entire society has been said about culture. It encompasses manners, rituals, and artistic standards.
The invention of farming helps feed large populations of humans and is an example of how culture can help humans survive.
Hence option A is correct.
To learn more about the culture refer to:
brainly.com/question/12678729
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