Answer:
The efficiency is 0.33, or 33%.
Explanation:
From the thermodynamics equations, we know that the formula for the efficiency of a heat engine is:

Where η is the efficiency of the engine, Q_1 is the heat energy taken from the hot source and Q_2 is the heat energy given to the cold object. So, plugging the given values in the formula, we obtain:

This means that the efficiency of the heat engine is 0.33, or 33% (The efficiency of an engine is dimensionless).
Do you remember this formula for the distance traveled while accelerated ?
<u>Distance = (initial speed) x (t) plus (1/2) x (acceleration) x (t²)</u>
I think this is exactly what we need for this problem.
initial speed = 20 m/s down
acceleration = 9.81 m/s² down
t = 3.0 seconds
Distance down = (20) x (3) plus (1/2) x (9.81) x (3)²
Distance = (60) plus (4.905) x (9)
Distance = (60) plus (44.145) = 104.145 meters
Choice <em>D)</em> is the closest one.
I'm trying to think of something that will give you the biggest bang for your buck, meaning what would give you the most number of energy transformations in their use.
Wind energy uses those great big windmills that transform wind into electrical energy. The wind is caused by the sun (which has nuclear energy, light energy and the earth's rotation which is not related to the sun but is mechanical energy). To start with you use mechanical energy. That energy drives a generator that stores it's energy in a battery. You have changed electrical energy into chemical energy. The batteries, on a calm day take over and provide electrical energy that must be transported to the consumers using it. Proponents of wind energy say that it is pollution free. It's not exactly true. The batteries used have to be manufactured (not a clean industry) and when they wear out, they pollute the environment if they cannot be recharged with new battery plates and acid (chemical).
Added to which wind energy is very noisy (sound energy) which has been linked to serious diseases.
The guy that answered this is fake and he’s doing it for free points so
Just repost it and hope he doesn’t find it