It has been proposed to use large inductors as energy storage devices. (b) If the amount of energy calculated in part (a) is stored in an inductor in which the current is 80.0 A, what is the inductance?

Video transcript

Hey, everyone. So this problem is working with energy and inductor. Let's see what it's asking us. A solenoid is used to store 1.25 times 10 to the sixth Jews of energy in a uniform magnetic field. The solenoid is supplied with 50 amps of current. And we're asked to determine the inductance. Our multiple choice answers here are a 1000 H B five times 10 to the 4h C 50 H or D one H. OK. So this is a straightforward problem. As long as we can recall that the equation for energy stored in an inductor is given by U the energy is equal to one half L, the inductance multiplied by I the current and that I term is squared. So we can rearrange this problem to isolate L the inductance, which is what we're solving for. And it becomes L equals to U divided by I squared. And then from there, we can just plug and play. So two multiplied by our energy given in the problem 1.25 times 10 to the six Jules divided by our current I 50 amps. And that term is squared, plug that into our calculator and we are left with 1000. We're looking at our multiple choice answers that aligns with answer choice. A that's all we have for this one. We'll see you in the next video.