A straight wire along the y-axis carries a current of 4 A. The wire is placed in a uniform magnetic field (0.02 T) \((\hat{\mathrm{i}}+\hat{\mathrm{j}})\). If the current in the wire is directed towards the negative y-axis, the force per unit length on the wire is
A. zero
B. – (0.08 N/m) \(\hat{\mathrm{k}}\)
C. (0.08 N/m) \((\hat{\mathrm{i}}-\hat{\mathrm{j}})\)
D. (0.08 N/m) \(\hat{\mathrm{k}}\)
Answer:D
A straight wire along the y-axis carries a current of 4 A. The wire is placed in a uniform magnetic field (0.02 T) \((\hat{\mathrm{i}}+\hat{\mathrm{j}})\). If the current in the wire is directed towards the negative y-axis, the force per unit length on the wire is
A. zero B. – (0.08 N/m) \(\hat{\mathrm{k}}\) C. (0.08 N/m) \((\hat{\mathrm{i}}-\hat{\mathrm{j}})\) D. (0.08 N/m) \(\hat{\mathrm{k}}\)