calculating magnetic fields (1 Viewer)

waltssillyhat

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"A 30 cm long solenoid with a 2 cm diameter is to produce a 0.2 T magnetic field in its centre. If the maximum current is 8 A, how many turns must the solenoid have? (Assume that each coil is circular rather than helical.)"

I know that I have to use the formula B = (μNI)/L, but I don't understand where to use the given of the diameter. Do I use it to determine how much current the solenoid can handle? If so, how would I approach doing this?
 

coolcat6778

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"A 30 cm long solenoid with a 2 cm diameter is to produce a 0.2 T magnetic field in its centre. If the maximum current is 8 A, how many turns must the solenoid have? (Assume that each coil is circular rather than helical.)"

I know that I have to use the formula B = (μNI)/L, but I don't understand where to use the given of the diameter. Do I use it to determine how much current the solenoid can handle? If so, how would I approach doing this?
I think u just use the formula B = (μNI)/L
 

cheesynooby

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"A 30 cm long solenoid with a 2 cm diameter is to produce a 0.2 T magnetic field in its centre. If the maximum current is 8 A, how many turns must the solenoid have? (Assume that each coil is circular rather than helical.)"

I know that I have to use the formula B = (μNI)/L, but I don't understand where to use the given of the diameter. Do I use it to determine how much current the solenoid can handle? If so, how would I approach doing this?
I think it's a red herring
 

coolcat6778

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the diameter is irrelevant. The formula B = (μNI)/L is made for calculating stuff at the centre, which you are given the values for
 

coolcat6778

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yeah but tbh yr 12 phys in general is a huge step up compared to yr11 (or maybe just my opinion)
not really, i think year 11 physics is more math heavy while year 12 is less math heavy because module 7 and 8 are memorization and rote learning heavy instead.

year 11 physics has collisions (which can even be in 2d) circuits and snell's law, which imo are the hardest parts of high school physics

the HSC exams would be more differentiating if the prelim content was tested in lieu of the garbage 8 + 5 marker module 8 or 7 history questions
 
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C2H6O

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not really, i think year 11 physics is more math heavy while year 12 is less math heavy because module 7 and 8 are memorization and rote learning heavy instead.

year 11 physics has collisions (which can even be in 2d) circuits and snell's law, which imo are the hardest parts of high school physics

the HSC exams would be more differentiating if the prelim content was tested in lieu of the garbage 8 + 5 marker module 8 or 7 history questions
yeah thats valid
 

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