Answer:
C. Waves transfer energy, but not matter.
Explanation: hope this helps :)
Answer:
a) variation of the energy is equal to the work of the friction force
b) W = Em_{f} -Em₀
, c) he conservation of mechanical energy
Explanation:
a) In an analysis of this problem we can use the energy law, where at the moment the mechanical energy is started it is totally potential, and at the lowest point it is totally kinetic, we can suppose two possibilities, that the friction is zero and therefore by equalizing the energy we set the velocity at the lowest point.
Another case is if the friction is different from zero and in this case the variation of the energy is equal to the work of the friction force, in value it will be lower than in the calculations.
b) the calluses that he would use are to hinder the worker's friction force and energy
W = Em_{f} -Em₀
N d = ½ m v² - m g (y₂-y₁)
y₂-y₁ = 35 -10 = 25m
c) if there is no friction, the physical principle is the conservation of mechanical energy
If there is friction, the principle is that the non-conservative work is equal to the variation of the energy
A drummer would loosen the drum skin in order to make the sound of a drum give a note of lower pitch.
However, I am not entirely sure.
Use the formula t = d/v
t = 15 km/ 37 km/h
t = 0.4054
t = 0.41 h (rounded)
Answer
given,
Area = 0.7 m²
electric field of wave = 0.0400 V/m
time = t =30 s
intensity of electromagnetic wave
c is speed of light
I = 4.24 x 10⁻⁶ W/m²
the amount of energy required
E = I A t
E = 4.24 x 10⁻⁶ x 0.7 x 30
E = 8.9 x 10⁻⁵ J
