The magnetic induction at a distance of 0.1 m from a straight wire through which 10A current
flows is:
A) 0.2 x 10^‐5T
B) 2 x 10^ ‐5T
C) 0.02 x 10^‐5T
D) 0.002 x 10^‐5T

Question

The magnetic induction at a distance of 0.1 m from a straight wire through which 10A current
flows is:
A) 0.2 x 10^‐5T
B) 2 x 10^ ‐5T          
C) 0.02 x 10^‐5T
D) 0.002 x 10^‐5T

anonymous · Answer

for a straight wire magentic field B at a distance of 0.1 m away is given by,
B = mu(I)/2(pi)r where I is the current and r the radial distance from the wire.plugging the values in the equation gives you
B=10^(-7) *2*10/0.1                    (as mu/2(pi) = 2*10^(-7))
B=2*10^-5T