Engineering Board Exam Reviewer · Physics · medium
What is the magnetic field 5 cm from a long straight wire carrying 10 A? ( 0 = 4π × 10-7 T· m/A)
- 40 T
- 251.3 T
- 20 T
- 0.40 T
Answer
A. 40 T
Solution
B = 0I/(2π r) = (4π × 10-7)(10)/(2π × 0.05) = 4.0 × 10-5 T = 40 T.
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