Answer:
It's placed on a building and connected with the ground below to protect the building from being damaged by lightning.
Hydrogen gas is harmless to your feet so since you don’t need protection against it that seems the best answer.
Answer:
C Don't worry if you thought it was D. I almost answered that.
Explanation:
Remark
You can get this just by learning the vocabulary.
Efficiency = Work Out / Work In * 100%
Work in = 30J That's you swinging the hammer.
Work out = 10 J That's how much of the hammer's work gets to the nail.
Efficiency = (10/30)*100
Efficiency = 1/3 * 100
Efficiency = 33%
Answer:
the height h is 1.95 m above the floor
Explanation:
m = 2.0 kilogram
Ep = 39 J
g = 10 m/s²
h = ?
Ep = mgh
h = Ep ÷ mg
h = 39 ÷ (2×10)
h = 39÷20
h = 1.95 m
Answer:
-730KJ
Explanation:
According to the first law of thermodynamics;
Let the total energy of the system be ∆E
Let heat be q and let work the w
Since the energy decreases ∆E is negative
Since work is done on the system w= positive
So;
- 250 = 480 + q
q = -250 - 480
q=-730KJ