Calculating Magnetic Field of a Solenoid: Where Did I Go Wrong?

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To calculate the magnetic field of a solenoid measuring 77.1 cm in length, with 340 turns and a radius of 1.92 cm, the formula used is B = (μ₀ * N * I) / l. The user initially calculated the magnetic field using the correct formula but received an incorrect result from a homework program. After re-evaluating, they found the answer to be 0.001 T. However, the program indicated that this answer was also wrong, leading to confusion about the calculation's accuracy. The discussion highlights the importance of verifying calculations and understanding the parameters involved in magnetic field equations.
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A solenoid 77.1 cm long has 340 turns and a radius of 1.92 cm. If it carries a current of 1.85 A, find the magnetic field along the axis at its center. Answer in units of T.
I know the formula for the magnetic field is:
Magnetic field = permeability x turn density x current
I entered -
B=(1.25664x10^-6)(340/.771)(1.85)
Where did I go wrong?
 
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Magnetic field = permeability x turn density x current

I think you could use this

B = \frac{\mu_0.I.N}{l}
 
Last edited:
ranger said:
I think you could use this

B = \frac{\mu_0.I.N}{l}

:-p He DID use that formula. You just reproduced what he said in words using symbols.
 
lw11011 said:
Where did I go wrong?

Looks ok so far. What makes you think that you went wrong? You didn't even post an answer, so it is not at all clear from your post what the problem is.
 
cepheid said:
:-p He DID use that formula. You just reproduced what he said in words using symbols.

:biggrin: I stand corrected :approve:
 
By using that formula I got the answer, 0.001 T. The computer program for our homework said the answer was wrong.
 

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