A steady current I goes through a wire loop PQR having shape of a right angle triangle with PQ = 3x, PR = 4x and QR = 5x. If the magnitude of the magnetic field at P due to this loop is k find the value of k. `((mu_(0)I)/(48pix))` find the value of k.

Answer

7

Explanation

Magnetic field at point P due to wires RP and PQ is zero. Only wire QR will produce magnetic field at P.
`r=3xxcos 37^(@)=(3x)(4/5)=(12x)/5`
Now `B=(mu_(0))/(4pi) I/(12x//5)[sin 37^(@)+sin 53^(@)]=7((mu_(0)I)/(48pix))`