# A 2.0-kg rod has a length of 1.0 m and a resistance of 4.0 Î©. It slides

```A 2.0-kg rod has a length of 1.0 m and a resistance of 4.0 Ω. It slides with constant
speed down a pair of frictionless vertical conducting rails that are joined at the bottom.
Other than the rod, the rest of the circuit is resistanceless. A uniform magnetic field of
magnitude 3.0 T is perpendicular to the plane formed by the rod and the rails as
shown.
a) Determine the value and direction of the current.
b) Determine the speed of the rod.
N
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What if the current loop will be closed from above, rather than on the bottom? Now, the area is
increasing. The same weight and resistance. Determine the value and direction of the current.
Process of growing current through an inductor
EMF-IR-L(ΔI/Δt)=0
How much power generates the EMF-source in the initial moment? How much power after a large time
of working when the current saturates? How much in the middle of the process (let us say in the
moment when I= Ifinal /2). How much power gets the inductor at the initial, intermediate and final stages
of the process?
Process of decaying the current passing through an inductor
-IR-L(ΔI/Δt)=0
How much power generates the inductor in the initial moment? How much in the middle of the process
(let us say in the moment when I= Iinitial /2). How much power it generates after a large time of working
when the current vanishes?
```