Answer:
Here is the complete question:
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a) Current for long straight wire
b) Current at the center of the circular coil
c) Current near the center of a solenoid
Explanation:
⇒ Magnetic Field due to long straight wire is given by (B),where
Plugging the values,
Conversion ,and
⇒Magnetic Field at the center due to circular coil (at center) is given by,
So
⇒Magnetic field due to the long solenoid,
Then
So the value of current are ,
and
respectively.