Using KE = 1/2mv^2
m = mass (80kg)
v = velocity (?)
KE = kinetic energy (2500J)
2500/((1/2) x (80)) = v^2
Square root the answer to get: 7.91 m/s
Answer:
c) True. If the coating cancels the light requested by the reflection, so there is more energy to enter the cell and therefore its efficiency increases
Explanation:
This exercise asks to analyze the effect of the antireflective coating on the efficiency of solar cells.
Let's start by expressing the expression for the interference of two light beams taken at when
* the phase change introduced when passing from air to 180º film
* the wavelength change by the refractive index of the film ln = lo / n
therefore the expression for destructive interference is
2 n t = m λ
where m is an integer
with these concepts we can analyze the different statements
a) False. Phase shift does not change the wavelength of light
b) False. The refractive index of the solar cell is not affected by the refractive index of the film since the two materials do not mix.
c) True. If the coating cancels the light requested by the reflection, so there is more energy to enter the cell and therefore its efficiency increases
d) false. In solar cells the incidence is almost normal, therefore the effect of refraction (separation of colors for different angles) is very small
Answer:
≈ 0.144 m
Explanation:
Density is mass divided by volume:
D = M / V
Solving for volume:
V = M / D
Given M = 1.2 kg and D = 400 kg/m³:
V = 1.2 kg / (400 kg/m³)
V = 0.003 m³
Volume of a cube is the side length cubed:
V = s³
Therefore:
s³ = 0.003 m³
s ≈ 0.144 m
Round as needed.
Answer:
a.
Explanation:
a
The property of air mass include
1) it must be large.
2) it must have relatively uniform properties.
3)it must travel as a recognizable entity.
It must have a warm front at its leading edge, is not necessarily a property of an air mass because Not all air masses have a warm front at their leading edge. There are five types of air masses and different types of the front can be developed.
First we can calculate the average speed v in km/h by the equation v=s/t where s is the distance traveled and t is the time:
First we turn time into seconds and divide by 3600 to get time t in hours is:
t=13*3600 s + 4*60 s + 58 s= 47098 s and that is:
t=47098s/3600s=13.08278 hours
So v=1633.8/13.08278=124.88 km/h
To get speed in m/s we simply turn kilometers into meters and hours into seconds:
s=1633.8 km *1000 = 1633800 m
t=13*3600s + 4*60 s + 58 s=46800 s + 240 s + 58 s=47098 s
v=s/t=1633800/47098=34.67 m/s
So average speed in km/h is v=124.88 km/h and in m/s is v= 34.67 m/s.
