MHB I do not recognize:$$B=\frac{\mu_0 I R^2}{2 R}$$Where did you find it?

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The discussion revolves around understanding the application of different magnetic field formulas related to current-carrying wires and loops. The user is confused about how to properly utilize the given radii and determine the magnitude of the magnetic field using the formulas provided. Clarifications are sought regarding the meaning of symbols and the context in which the formulas are applied. The correct formula for a straight wire is identified, while another formula presented is questioned for its origin. The conversation emphasizes the need for clarity in symbols and context to effectively solve the problem.
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When dealing with uniform displacement:
I get confused as too know exactly how find and properly utilize the given radii.
Determine the magnitude
i.e.:
given:
R=3.00cm
id=.500A
r=radial distances of displacement 2.00cm, 500cm

b=(mu id)/2pi r
b=(mu id) R^2/2pi r

there are two different variations of the formula^ that correlate with the given parameters. How do I approach this problem? What context clues do I need to look for?
 
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nerdsamurai22 said:
When dealing with uniform displacement:
I get confused as too know exactly how find and properly utilize the given radii.
Determine the magnitude
i.e.:
given:
R=3.00cm
id=.500A
r=radial distances of displacement 2.00cm, 500cm

b=(mu id)/2pi r
b=(mu id) R^2/2pi r

there are two different variations of the formula^ that correlate with the given parameters. How do I approach this problem? What context clues do I need to look for?

Hi nerdsamurai22! Welcome to MHB! :)

Can you clarify what your symbols represent?
Do you perhaps have a drawing?Anyway, the formula:
$$B=\frac{\mu_0 I}{2\pi r}$$
belongs to a straight wire with current $I$. It gives the magnetic field $B$ at distance $r$ from the wire.I do not recognize:
$$B=\frac{\mu_0 I R^2}{2\pi r}$$
Where did you find it?Furthermore, the formula:
$$B=\frac{\mu_0 I}{2 R}$$
gives the magnetic field strength in the center of a wire loop with radius $R$ carrying current $I$.
 
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