Why is the starting current of an ideal transformer with an open secondary switch equal to zero?
Explanation
This question explores the behavior of an ideal transformer under no-load conditions, linking the absence of secondary current to the absence of primary current based on the zero-net-mmf assumption.
Other questions
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A toroidal core has a relative permeability of 6000, a mean length of 23.5 cm, and a cross-sectional area of 6 x 10^-4 m^2. Calculate the reluctance of the core. The permeability of free space is 4pi x 10^-7 Wb/Am.
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What is the mechanical analog of an electrical transformer, as described in the text?
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How is the magnetic flux (Φ) passing through a surface area A generally defined?
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In an ideal transformer, the total mmf applied to the core is F = N1i1(t) - N2i2(t). Why is this total mmf considered to be zero?
What is the relationship between the developed power (Pdev), the air-gap power (Pag), and the slip (s) in an induction motor?
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What is the key assumption about an ideal transformer's power efficiency?
The energy W delivered to a coil with N turns and zero resistance is given by the integral of Ni dΦ. If Ni = Hl and dΦ = AdB, where l is the mean path length and A is the cross-sectional area, what is the resulting expression for energy per unit volume, Wv?