Answer:
1.778 times more or 16/9 times more
Step-by-step explanation:
Given:
- Mirror 1: D_1 = 8''
- Mirror 2: D_2 = 6"
Find:
Compare the light gathering power of an 8" primary mirror with a 6" primary mirror. The 8" mirror has how much light gathering power?
Solution:
- The light gathering power of a mirror (LGP) is proportional to the Area of the objects:
LGP ∝ A
- Whereas, Area is proportional to the squared of the diameter i.e an area of a circle:
A ∝ D^2
- Hence, LGP ∝ D^2
- Now compare the two diameters given:
LGP_1 ∝ (D_1)^2
LGP ∝ (D_2)^2
- Take a ratio of both:
LGP_1/LGP_2 ∝ (D_1)^2 / (D_2)^2
- Plug in the values:
LGP_1/LGP_2 ∝ (8)^2 / (6)^2
- Compute: LGP_1/LGP_2 ∝ 16/9 ≅ 1.778 times more
Answer:
0.0057
Step-by-step explanation:
- Narrow it down.
- The point P is between 5 * 10^-3 and and 6*10^-3
- When you go to the bottom line, P is on the 7th division from the left.
- Going from left to right increases P
- P is on a line that goes between 5 and 6. Each division is 1/10. So P is in the tenth place.
- One of the answers is 5.7 * 10^-3
- The other answer is .0057
- I really don't know which one to choose because we are given no direction. As a programmer, 0.0057 would be easier to program. I would choose it.
- If it is not correct, then 5.7 * 10^-3 is the answer.
The answer is A. 7
so y=7
3.045*10^-3 is the scientific notation
