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Given is a single-phase transformer with the winding numbers n₁ = 1000 and n₂ = 100. This transformer is intended to be used for supplying a 24 V lighting system from the low-voltage power grid (outlet).

a) Sketch a possible practical construction of the transformer. Label the components and indicate the general direction of the magnetic field.

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Final answer:

The question pertains to transformers and constructing a diagram for one with a primary to secondary turn ratio of 1000:100. It also requires solving for secondary winding turns and primary current in a step-up transformer scenario.

Step-by-step explanation:

Transformers, specifically to sketching and labeling a transformer construction and addressing a step-up transformer problem. Given a primary to secondary winding ratio of 1000:100, the transformer is meant to adapt a low-voltage power grid output to a 24 V lighting system.

Sketch and Components

A practical construction of a transformer includes:

  • A soft iron core which is typically laminated to minimize eddy currents.
  • Primary winding with n1 turns, connected to the alternating current (AC) power source.
  • Secondary winding with n2 turns, where the induced voltage supplies the load (the lighting system).

The direction of the magnetic field in a transformer is determined by the current's direction in the primary winding and the right-hand rule. Changes in the primary current result in a changing magnetic field, which induces a current in the secondary winding.

To solve for the number of secondary winding turns in a step-up transformer, the formula Ns / Np = Vs / Vp is used, where Ns and Np are the number of turns on the secondary and primary windings, and Vs and Vp are the secondary and primary voltages respectively.

(a) The ratio of secondary to primary turns required to step the voltage up from 110 V to 2000 V with 100 turns in the primary is calculated as:

Ns = (2000 V / 110 V) × 100 turns = 1818.18 turns (approximately).

(b) The primary current can be determined using the power equivalence Pp = Ps and the formula Ip = Ps / Vp, where Ps is the secondary power and Ip is the primary current. If the secondary winding draws a current of 0.75 A at 2000 V, the primary current is calculated as:

Ip = (0.75 A × 2000 V) / 110 V = 13.64 A (approximately).

User Jefferson Houp
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Faraday's law of induction is a basic law of electromagnetism that show how a magnetic field will interact with an electric circuit to produce an electromotive force.

N1= Primary Winding

N2= Secondary Winding

The diagram has Yoke, terminals and a general direction of Magnetic Field.

The magnetic field generated by the primary winding passing through the core alternates in direction with the AC current. This changing magnetic field induces an AC voltage in the secondary winding due to electromagnetic induction.

The direction of the induced voltage and current in the secondary winding is opposite to the primary winding according to Faraday's Law.

Given is a single-phase transformer with the winding numbers n₁ = 1000 and n₂ = 100. This-example-1
User Jeschwar
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