Answer:
25
Step-by-step explanation:
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:
1 hour and 45 mins
Step-by-step explanation:
As mentioned,
Starting time = 2:30 PM
Ending time = 4:15 PM
The given time is in hours and minutes, to calculate the duration of movie, time should be converted into a same unite minutes.
1 hour = 60 minutes
Therefore,
2:30 = 2 hours and 30 mins = 2*60 + 30 mins = 150 mins
4:15 = 4 hours and 15 mins = 4*60 + 15 mins = 255 mins
The duration = Ending time - Starting time
=> 255 - 150
=> 105 mins
or
60 + 45
1 hour and 45 mins
