Sail E0 Webinar
Question
Figure shows a square loop ABCD with edge length a. The resistance of the wire ABC is r and that of ADC is 2r. The value of magnetic field at the centre of the loop assuming uniform wire is
Figure Shows A Square Loop ABCD With Edge Length A. The Resi...
 
Options:
A .  √2μ0i3πa⊙  
B .  √2μ0i3πa⊗  
C .  √2μ0iπa⊙  
D .  √2μ0iπa⊗
Answer: Option B
:
B
According to question resistance of wire ADC is twice that of wire ABC. Hence current flows through ADC is half that of ABC i.e. i2i1=12. Also i1+i2=ii1=2i3 and i2=i3
Magnetic field at centre O due to wire AB and BC (part 1 and 2) B1=B2=μ04π.2i1sin45a/2=μ04π.22i1a
and magnetic field at centre O due to wires AD and DC (i.e. part 3 and 4) B3=B4=μ04π22I2a
Also i1=2i2. So (B1=B2)>(B3=B4)
Hence net magnetic field at centre O
Bnet=(B1+B2)(B3+B4)
=2×μ04π.22×(23i)aμ04π.22(i3)×2a
=μ04π.42i3a(21)=2μ0i3πa

Was this answer helpful ?
Next Question

Submit Solution

Your email address will not be published. Required fields are marked *

More Questions on This Topic :


Latest Videos

Latest Test Papers