Ohhh okay
How do you find the strength of an electromagnetic field?
What would be the strength of the magnetic field if the electromagnet was 200 cm, has 10 amps running through it, and has 400 coils?
Nice, your turn-Ohhh okay
How do you find the strength of an electromagnetic field?
What would be the strength of the magnetic field if the electromagnet was 200 cm, has 10 amps running through it, and has 400 coils?
- Answer
Reviving... what does Coulomb's law state?
Yep, your turnReviving... what does Coulomb's law state?
- Answer
They always apply?
- Question
No, there are some cases where they don't apply. With KVL, it doesn't apply with a varying magnetic field, and with KCL, it doesn't apply when the voltage source has a very high frequency. Anyways, your turn!They always apply?
- Question
Whoops...No, there are some cases where they don't apply. With KVL, it doesn't apply with a varying magnetic field, and with KCL, it doesn't apply when the voltage source has a very high frequency. Anyways, your turn!They always apply?
- Question
So this isn't relevant to the next question, but I think it's informative to clarify the statement about KVL not holding. The issue seems a bit more complicated than KVL being invalid in some cases. KVL ostensibly doesn't hold in the situations mentioned above because there are parasitic inductances that come into play that the normal lumped element model of resistors does not take into account. If the model is made more realistic by adding in these inductances and we are careful with how we define voltages and KVL, then indeed, KVL still holds within a varying magnetic field or with high frequency sources since it is dependent on a conservation of energy argument. It ultimately boils down to the model being insufficient to explain everything that is happening in the circuit rather than a problem with KVL.No, there are some cases where they don't apply. With KVL, it doesn't apply with a varying magnetic field, and with KCL, it doesn't apply when the voltage source has a very high frequency. Anyways, your turn!They always apply?
- Question
Thanks for the links! Always glad to see people still helping out with Science Olympiad after high school (assuming you did Science Olympiad in high school?)So this isn't relevant to the next question, but I think it's informative to clarify the statement about KVL not holding. The issue seems a bit more complicated than KVL being invalid in some cases. KVL ostensibly doesn't hold in the situations mentioned above because there are parasitic inductances that come into play that the normal lumped element model of resistors does not take into account. If the model is made more realistic by adding in these inductances and we are careful with how we define voltages and KVL, then indeed, KVL still holds within a varying magnetic field or with high frequency sources since it is dependent on a conservation of energy argument. It ultimately boils down to the model being insufficient to explain everything that is happening in the circuit rather than a problem with KVL.No, there are some cases where they don't apply. With KVL, it doesn't apply with a varying magnetic field, and with KCL, it doesn't apply when the voltage source has a very high frequency. Anyways, your turn!They always apply?
This issue actually turned into quite a big discussion online which resulted in a very in-depth look at a series of definitions and experiments. A whole lot more can be found at the following places:
ElectroBOOM's Initial Assertion
Followup video
Relevant paper by MIT Professor John Belcher in response
In any case, sorry about the interruption to the question chain. Please carry on.
1)Whoops...No, there are some cases where they don't apply. With KVL, it doesn't apply with a varying magnetic field, and with KCL, it doesn't apply when the voltage source has a very high frequency. Anyways, your turn!They always apply?
Calculate the electric field strength 1 micrometer from a proton (e=1.6e-19 C).
If a proton is moving east at 300 m/s and experiences an acceleration of 2.6e10 m/s^2 south, what is the strength and direction of the B-field (the mass of a proton is 1.67e-27 kg)?
I probably should've given Coulomb's constant in the problem... But I think east and south are always orthogonal, no? Anyway, your turn!1)Whoops...
No, there are some cases where they don't apply. With KVL, it doesn't apply with a varying magnetic field, and with KCL, it doesn't apply when the voltage source has a very high frequency. Anyways, your turn!
Calculate the electric field strength 1 micrometer from a proton (e=1.6e-19 C).
If a proton is moving east at 300 m/s and experiences an acceleration of 2.6e10 m/s^2 south, what is the strength and direction of the B-field (the mass of a proton is 1.67e-27 kg)?
Given ...
2)
There are multiple answers here since the angle between the magnetic field and the velocity vector was not given. So I'll make this simple and say they are orthogonal to each other ().
Now according to the Right Hand Rule, if the proton is moving east and is experiencing a force south, the magnetic field must be out of the page.
pointed out of the paper.
Yes you are definitely correct that east and south are orthogonal, but in the case of the Right Hand "Slap" Rule...(my Physics teacher was great )I probably should've given Coulomb's constant in the problem... But I think east and south are always orthogonal, no? Anyway, your turn!Whoops...
Calculate the electric field strength 1 micrometer from a proton (e=1.6e-19 C).
If a proton is moving east at 300 m/s and experiences an acceleration of 2.6e10 m/s^2 south, what is the strength and direction of the B-field (the mass of a proton is 1.67e-27 kg)?
- Answer
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