The correct answer is 100 N.
In fact, the problem already says that the force exerted by magnet A on magnet B is exactly 100 N. The information about the magnetic field intensity of the two magnets is redundant, because we are interested only in the magnitude of the force.
Answer:
Part A: D
Part B: W = Qh - Qc
Part C: e = 1 - Qc/Qh
Explanation:
The heat engine is the engine that transforms heat (Q) in work (W), and by the second law of the thermodynamics, its efficiency can not be 100%, it means that some heat must be dissipated.
Part A:
The engine works with two sources of heat, one hot (Qh) at a hot temperature (Th) and another cold (Qc) at a cold temperature (Tc). It is necessary so, the hot source will give energy to the fluid of the engine, and the cold source will be the source where these heat will dissipate and the fluid will return to its original temperature. So,
Qh > Qc, and Th > Tc
Part B:
The ideal heat engine is the one that can use the most amount of heat to transform it at work. It is characterized by Qh/Qc = Th/Tc.
The work is the useful energy, so it is the total heat (Qh) less the heat dissipated (Qc):
W = Qh - Qc
Part C:
The effiency is the useful energy divided by the total energy. Because W = Qh - Qc:
e = W/Qh
e = (Qh - Qc)/Qh
e = Qh/Qh - Qc/Qh
e = 1 - Qc/Qh
I think the correct answer from the choices listed above is the last option. When electrical energy is converted into thermal energy, the <span>total amount of thermal energy plus electrical energy doesn't change. This is base on the Law of Conservation of energy where energy cannot be created or destroyed. </span>
B. Mentally represent their environment
Correct answer is 2.7 x 10^-3 J/m3
I hope that helps ! <33