00:01
Here in this given problem first of all this is the semicircular portion of the wire and this is the straight portion in the form of the diameter of this semicircle.
00:14
And magnetic field in this region that is along the y axis the semicircular loop itself that is in the x y plane diameter of this semicircle that is along x axis.
00:35
So, the direction of magnetic field that is upward radius of the semicircle that is r.
00:50
So, if we consider this diameter to be ab that diameter will be given as twice of r current passing through this loop that is i and magnetic field that is given to be b which is upward along y axis positive y axis ok.
01:35
In the first part of the problem we have to find magnetic force acting on a straight portion means at diameter straight portion which is ab that will be given by f in vector form that is current element current element will be the current is passing from a to b.
02:15
So, this is the current element cross b means cross product of current element with the magnetic field vector.
02:24
So, we can say this f is equal to i multiplied by 2r multiplied by b and angle between them that is 90 degree.
02:34
So, this force is given as f is equal to twice of b i r magnitude of the force and this force using fleming's left hand rule this force is directed upward outward out of the perpendicularly out of the plane of paper or we can say outward along positive z axis ok.
03:23
Now, in the second part of the problem we have to find magnetic force on the curved path on the curved portion and to find it we use calculus method we differentiate this wire into small segment and then select one such small current element at an angle theta from the positive x axis and suppose this small element current element i d l that is making small sector angle d theta at the center of this semicircular loop ok...