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1. The problem statement, all variables and given/known data

Question 1: A telescope has a focal length of 18m. If the suns diameter is about 1.39 x 10^9m and its distance from Earth is 1.49 x 10^11, how large is the telescopes image of the sun.

2. A converging mirror produces an image twice the size of the obbect. If the focal length is 20cm, find the object distance.

2. Relevant equations

1/f = 1/do + 1/di

m = -di/10 = hi/10

- FOR BOTH

3. The attempt at a solution

f = 18m

do = 1.49 x 10^11

ho = 1.39 x 10^9

1/f = 1/do + 1/d1

1/f - 1/do = 1/di

-0.56 = di

m = - (di)/do

= - (-0.56m / 1.49 x 10^11)

3.76 x 10 = m

m = hi / ho

3.76 x 10 ^10 = hi / 1.39x 10 ^...

THE FINAL ANSWER FOR THE QUESTION IS 17CM

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Telescope focal length homework

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