Flux density from flux and area: In a magnetic field, a flux of 600 µWb passes through an area of 0.1 m^2. Calculate the flux density B.
-
A6,000 µT
-
B600 µT
-
C6 T
-
D600 T
-
E60 µT
Answer
Correct Answer: 6,000 µT
Explanation
Introduction / Context:Flux density B quantifies how much magnetic flux passes per unit area and is a central concept in electromagnetics, affecting induced voltages and magnetic forces. It connects the physical flux to field intensity via the area considered.
Given Data / Assumptions:
- Total magnetic flux, phi = 600 µWb = 600 * 10^-6 Wb.
- Area, A = 0.1 m^2.
- Uniform flux distribution is assumed over the area for a straightforward calculation.
Concept / Approach:
By definition, B = phi / A. Convert all units to SI before dividing. 1 tesla (T) equals 1 Wb/m^2. You can also express the result in microtesla (µT) for convenience, where 1 T = 10^6 µT.
Step-by-Step Solution:
Convert flux: phi = 600 µWb = 600 * 10^-6 Wb = 6 * 10^-4 Wb.Compute B: B = phi / A = (6 * 10^-4) / 0.1 = 6 * 10^-3 T.Convert to µT: 6 * 10^-3 T = 6 * 10^3 µT = 6,000 µT.Verification / Alternative check:
A quick order-of-magnitude check: micro–weber over a tenth of a square meter should yield milli–tesla or thousands of microtesla, consistent with 6,000 µT.
Why Other Options Are Wrong:
600 µT is a factor of 10 too small; 6 T and 600 T are far too large given the small flux and moderate area; 60 µT is two orders too small.
Common Pitfalls:
Missing the micro (10^-6) prefix or forgetting to divide by area correctly. Always standardize units first to avoid errors.
Final Answer:
6,000 µT