Magnetic Effects Of Current Question 136
Question: An infinitely long conductor PQR is bent to form a right angle as shown. A current I flows through PQR The magnetic field due to this current at the point M is H1. Now another infinitely long straight conductor QS is connected at Q so that the current is I/2 in QR as well as in QS, The current in PQ remaining unchanged. The magnetic field at M is now $ {H_{2.}} $ The ratio $ H_{1}/H_{2} $ is given by [IIT-JEE (Screening) 2000]
Options:
A) $ \frac{1}{2} $
B) 1
C) $ \frac{2}{3} $
D) 2
Show Answer
Answer:
Correct Answer: C
Solution:
Magnetic field at any point lying on the current carrying straight conductor is zero. Here H1 = Magnetic field at M due to current in PQ. H2 = Magnetic field at M due to QR + magnetic field at M due to QS + magnetic field at M due to PQ $ =0+\frac{H_{1}}{2}+H_{1}=\frac{3}{2}H_{1} $
Þ $ \frac{H_{1}}{H_{2}}=\frac{2}{3} $
BETA
