Solar energy is free and renewable.
Its efficiency is determined by the photovoltaic or heat-exchanging equipment used, and the efficiency of the infrastructure built to interconnect them. None of that depends on the time of the year. For a given amount of solar energy absorbed by the collector, the amount of useful output energy doesn't change with the season.
Wood, wind, sunshine,geothermal energy, biomass and water
Answer: Lily, Astrid, Henry, and Bob
Explanation:
By a small online search i've found the image related to this question, and you can see it below.
Joules is a unit of energy, such that:
Joule = kg*m^2/s^2
In other hand, Watt is a unit of power, such that:
1 W = 1 J/s
Then if we measure power, we are measuring watts, which is equivalent to measuring the total amount of energy in joules in a given period of time, and then dividing that by the time. And if we measure energy, we are directly measuring joules.
Then if we measure power or energy, at some point our measures will be in joules (unless we have an specific device to measure power, but these usually exist for electronic systems, not for mechanical/dinamic systems like the ones in the image), this means that all of them will record their measurements in joules, so the correct option is Lily, Astrid, Henry, and Bob
Given parameters:
Duration of crash = 9min
Velocity before crash = 2000 yards per second
Unknown:
Acceleration of the plane = ?
Solution:
Acceleration is the change of velocity with time.
Acceleration =
where v is the final velocity
u is the initial velocity
t is the time taken
We need to convert the time into seconds from min;
60s = 1 min
So, 9min = 60 x 9 = 540s
So input the parameters and solve;
Acceleration =
= 3.7yards/s²
The acceleration of the plane is 3.7yards/s²