<span>There are four laws of thermodynamic which define and characterize the thermodynamic system at thermal equilibrium.
The laws of thermodynamics state that, in a heat engine, </span>all the heat energy from a source cannot be converted to mechanical energy.
Google it and I bet you find the correct answer
I don’t understand can you please explain your question thank u
Answer:
When air resistance equals the weight of an object, the object has reached free fall.
Explanation:
- When an object has only force acting on it as gravity then, it experiences free fall.
- During free fall all the forces except gravity is balanced by one another.
- In the question, object's weight is balanced by air resistance so it is in the state of free fall.
- At the null point of free fall, object experiences weightlessness i.e. it feels like object is not attracted by any force.
Efficiency = useful energy out / total energy in x 100
= 100/400 x 100
=0.25 x 100
= 25%
25%
