- #1
Clara Chung
- 304
- 14
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Homework Statement
Homework Equations
Please review the question and answer of question 34.
The Attempt at a Solution
1.Why does the answer take the rated power as the power output?
2.I tried to find the current like this:
R=200^2 / 100 = 400 ohm
I at Q = 400/[2(400)] = 0.5 A
I at P = 0.5/2 = 0.25 A
3. As the approach as shown as (2) is wrong. Either V is not equal to IR in the circuit Q or the secondary voltage is not 400/2 = 200V.
4. As question 36 used a similar method as (2), V should be equal IR. So the only possibility is Vq not equal to Vp [Nq/Np].
5. However as the change of magnetic flux is the same everywhere in the iron core. By V=-NdΦ/dt.
Vp=- Np dΦ/dt...(a)
Vq=- Nq dΦ/dt...(b)
Vr=- Nr dΦ/dt...(c)
by (b)/(a)
Vq = Vp [Nq/Np]
6. So please tell me what's wrong. Thank you VERY much.