Consider a system consisting of two concentric very long solenoids, as illustrat
ID: 1377516 • Letter: C
Question
Consider a system consisting of two concentric very long solenoids, as illustrated below. The current in the outer solenoid is I1 = 1.25 A, and the current in the inner solenoid is I2 = 2.17 A. The number of turns per centimeter* is 120 for the outer solenoid and 79 for the inner solenoid.
*Be careful with this conversion.
(a) Find the magnitude and direction of the magnetic field between the solenoids.
18.85 mT left
(b) Find the magnitude and direction of magnetic field inside the inner solenoid.
____ mT right
Explanation / Answer
Here is how I think you can solve it.
n= 120/cm outer solenoid
n= 79/cm for inner solenoid.
A) B= uo*n* i -------> 4pi *10^-7* 1200*1.25/ 10^-4= 18.85 mT
B) B= B inner- B outer ----> 21.54-18.85= 2.7
B inner = 4pi *10^-7*790*2.17/10^-4=21.54