0:00
Hi there.
00:01
So for this problem, we are told that the flexible loop that is shown in this figure has a radius that is given and that radius is equal to 11 centimeters.
00:13
That in meters is 0 .11 meters.
00:18
And is in a magnetic field of magnitude that is also given and that magnitude is equal to 0 .18 tesla.
00:31
Loop is grabs at points a and b and stretch it until its area is nearly zero.
00:38
So there is going to be a change in the area for this case.
00:45
Now if it takes 0 .240 seconds, so we are given a time in this case, 0 .240 seconds to close the loop.
01:01
So the question is, what is the magnitude of the average induced emph in it during this time interval? so we start by knowing that the emph induced, the magnitude of the emph induced, is just simply the change in the magnetic loops divided by the interval of time.
01:32
The flups is defined as the product between the magnetic field, the area, and the cosine of the angle between these two quantities.
01:44
Now, in this case we have the change in the magnetic field.
01:51
So we know that the magnetic field is not changing.
01:59
It is a constant in this case, but the area is changing.
02:04
Because as the problem states, the loop is grabs at points a and b and stretch it until its area is nearly zero.
02:14
So we are going to have a final area that is equal to zero and an initial area that corresponds to the area of a circle that we know is just simply pi times its radius square.
02:27
So with that said, we can write that the mf -induced is just simply the magnetic field times the magnet of the change in the area times the cosine of the angle.
02:40
In this case, the cosine of the angle is going to be the cosine of zero because there is zero, because the angle between these two quantities is just simply zero...