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skinner
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A 40-turn, 4.0-cm-diameter coil with resistance R=.40 ohms surrounds a 3.0-cm-diameter solenoid. The solenoid is 20 cm long and has 200 turns. The 60 Hz current through the solenoid is I = I_0 * sin(2pi*f*t).
What is I_0 if the maximum current in the coil is 0.20 A?
Basically, there is a coil with N=40 turns, radius = .02 m, resistance = .40 ohms, and I_max = .20 A. That coil surrounds a solenoid with N = 200 turns, radius = .015 m, and length = .2 m. The current through the solenoid is given by I = I_0 * sin(2*pi*60*t). The problem asks for I_0.
I'm pretty sure it has something to do with V = -L*dI/dt.
I tried L = mu_0*(40*200)^2*.015^2*pi/.2
and dI/dt = 2*60*pi*I_0*cos(2*60*pi*t) = 2*60*pi*I_0 (we want initial current so t -> 0)
and V = IR = .2*.4
I am doing something wrong. There are no examples in the text like this, and I am pretty stuck. Any help would be appreciated. Thanks :)
What is I_0 if the maximum current in the coil is 0.20 A?
Basically, there is a coil with N=40 turns, radius = .02 m, resistance = .40 ohms, and I_max = .20 A. That coil surrounds a solenoid with N = 200 turns, radius = .015 m, and length = .2 m. The current through the solenoid is given by I = I_0 * sin(2*pi*60*t). The problem asks for I_0.
I'm pretty sure it has something to do with V = -L*dI/dt.
I tried L = mu_0*(40*200)^2*.015^2*pi/.2
and dI/dt = 2*60*pi*I_0*cos(2*60*pi*t) = 2*60*pi*I_0 (we want initial current so t -> 0)
and V = IR = .2*.4
I am doing something wrong. There are no examples in the text like this, and I am pretty stuck. Any help would be appreciated. Thanks :)