The gap between the two flasks is partially evacuated of air creating a near vacuum which significantly reduces heat transfer by conduction or convection
Answer:
D) 15s
Explanation:
let Te be the period of the block-spring system on earth and Tm be the period of the same system on the moon.let g1 be the gravitational acceleration on earth and g2 be the gravitational acceleration on the moon.
the period of a pendulum is given by:
T = 2π√(L/g)
so on earth:
Te = 2π√(L/g1)
= 6s
on the moon;
Tm = 2π√(L/g2)
since g2 = 1/6 g1 then:
Tm = 2π√(L/(1/6×g1))
= √(6)×2π√(L/(g1))
and 2π√(L/(g1)) = Te = 6s
Tm = (√(6))×6 = 14.7s ≈ 15s
Therefore, the period of the block-spring system on the moon is 15s.
Answer:
Average speed of car in the first trip is 10 km/hr
Explanation:
It is given that first the car drives 6 hours to the east
Then travels 12 km to west in 3 hours
Average speed for the entire trip = 8 km/hr
Total time = 3+6 = 9 hour
So distance traveled in 9 hour = 9×8 = 72 km
As the car travel 12 km in west so distance traveled in east = 72-12 = 60 km
Time by which car traveled in east = 6 hour
So speed 
So average speed of car in the first trip is 10 km/hr
Answer:
It demonstrates that the narrator is surrounded by nature.
Explanation:
Walt Whitman's "Crossing the Brooklyn Ferry" is a free verse poem written about the speaker's return trip on a ferry. He talks about his daily commute on the Brooklyn ferry, like the other commuters, and how they all share the same experience.
The given lines are from the very first stanza of the poem. The speaker repeats<em> "face-to-face" </em>when talking about nature. He sees the <em>"flood-tide below"</em> and the <em>"clouds"</em> high in the sky. This repetition demonstrates that he is surrounded by nature, amidst the throng of people around him. This shows the speaker's attitude of seeing the beauty of nature in any way he can, despite the bustle of commuting from Brooklyn to Manhattan.
Thus, the correct answer is the second option.