00:07
So here we have a section of the silver ribbon.
00:15
And we know that the drift velocity is related to the current density by this equation.
00:24
And current density is given by current over area which is equal to y1 times z1.
00:32
So using this equation we find the current density and use this value of current density in this equation to find the velocity.
00:41
And that comes out to be 4 .7 times 10 to the part minus 3 meter per second.
00:49
Now for the second part, we know that in order for the net force to be zero, the electric field is determined, we have to determine the electric field.
01:06
Sorry, in order for the net force to be zero, the electric force should be equal to to the magnetic force in magnitude, and the directions of these forces should be opposite to each other.
01:22
So we write these two forces, so electric forces, the magnitude of charge times the magnitude of electric field, and the magnetic force has magnitude qmod times, the drift velocity times, the magnetic field, which only has a component along wide direction.
01:44
And we simplify this equation and we find the electric field to be this value and we solve this and we get the magnitude of the electric field to be 4 .5 times 10 to the power minus 3 volts per meter.
02:03
Now for the direction, we know that the drift velocity of the electron is in the opposite direction to the current...