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Ib Physics Vocab
Section: Electromagnetism
Term | Definition |
---|---|
Magnitude of a Magnetic Field (Magnetic Field strength, Magnetic Field intensity, magnetic flux density ) (B) | ration of magnetic force on current carrying conductor to the product of the current and length of wire and sine of the angle between the current and the magnetic field (B = FB / Isinθ) (B = FB / qvsinθ) |
Direction of a Magnetic Field | the direction that the North pole of a small test compass would point if placed in the field IO (N to S) |
Magnetic Flux (Φ) | product of the magnetic field strength and a cross-sectional area and the cosine of the angle between the magnetic field and the normal to the area (Φ = B A cosθ) |
Magnetic Flux Linkage | product of the magnetic flux through a single coil and the total number of coils (flux linkage = N Φ) |
Faraday's Law | The emf induced by a time changing magnetic field is proportional to the rate of change of the flux Linkage ((ε α N ΔΦ/Δt) |
Lenz's Law | The direction of an induced emf is such that it produces a magnetic field whose direction opposes the change in magnetic field that produced it. (NOTE: This is the negative sign added to Faraday’s law. ε= - N ΔΦ/Δt) |
Root Mean Square (rms) Value of an Alternating Current (pr Voltage) | the value of the direct current (or voltage) that dissipates power in a resistor at the same rate (NOTE: The rms value is also known as the “rating.”) |