What can employers do to help ensure safety in a confined space? Employers can:
1 answer:
You might be interested in
Answer:
A=False
B=False
C=False
D=False
E=False
F=False
Explanation:
A. In an isothermal process, only the reversibly heat transfer is 0,
B. Consider the phase change of boiling water. Here, the temperature remains constant but the internal energy of the system increases.
C. This is not true even in reversible process, as can be inferred from the equation in part A.
D. This is only true in reversible processes, but not in all isothermal processes.
E. Consider the phase change of freezing water. Here, the surroundings are increasing their entropy, as they are taking in heat from the system.
F. This is not true if , like in answer B. One case where this is true is in the reversible isothermal expansion (or compression) of an ideal gas.
Answer:
a) E = b) i.
Explanation:
Assuming no other forces acting on the electron, as the field is pushing the electron back till it comes to rest momentarily, applying the work-energy theorem, the loss in kinetic energy, must be equal to the work done by the field on the electron.
The force that does work on the electron is the one due to the electric field E, and by definition of electric field, can be expressed as follows:
W = q*E = -e*E (1)
This work must be equal to the change in Kinetic Energy:
ΔK = Kf -K₀ = 0 - K = -K (2)
From (1) and (2), and solving for E, we have:
E =
b) As the electric field (by convention) has the direction that it would have a positive test charge, the electrons (being negative charges),when starting from rest),have the direction opposite to the field.
In this case, as the electron has an initial velocity, and the field is opposing to the electron movement, we conclude that the electric field is in the direction of the electron´s motion, due to the electron slows down, and then comes momentarily to an stop, before changing direction and move opposite to the field as it is its natural behavior.