A step-down transformer connected to a 120 V electric generator has 30 loops on the primary for each loop in the secondary. (a) What is the voltage of the secondary? (b) If the transformer has a 90.0 A current in the primary, what is the current in the secondary? (c) What are the power input and output?
(a)
The secondary voltage of a step-down transformer.
Answer to Problem 16PEB
Solution:
The secondary voltage is
Explanation of Solution
Given data:
A step-downtransformer with 30 loops for every loop at the primary side. The primary coil is supplied with
Formula used:
The expression that relates the number of loops and the voltage is written as,
Here,
Explanation:
Consider the expression.
Rearrange to get the secondary voltage
The number of loops at the primary and the secondary sides are dependent on each other.
Consider theloops at secondary side be
Substitute
Conclusion:
Hence, the secondary voltage is
(b)
The secondary current in the step-down transformer.
Answer to Problem 16PEB
Solution:
The secondary current is
Explanation of Solution
Given data:
A step-down transformer with 30 loops for every loop at the primary side. The primary coil is supplied with
Formula used:
The expression for power in a transformer is written as,
Here,
Explanation:
Consider the expression for power in the transformer.
Rearrange the power expression to get the secondary current
Substitute
Conclusion:
Hence, the current at the secondary side is
(c)
The power of the transformer at the input and the output sides.
Answer to Problem 16PEB
Solution:
The power at the input and the output side is same and is equal to
Explanation of Solution
Given data:
A step-down transformer with 30 loops for every loop at the primary side. The primary coil is supplied with
Formula used:
The expression for power at the input side is written as,
Here,
The expression for power at the output side is written as,
Here,
Explanation:
Consider the expression for the input power.
Substitute
Similarly, consider the expression for the output power.
Substitute
Conclusion:
Hence, the power at the input and the output side is same and is equal to
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Chapter 6 Solutions
EBK PHYSICAL SCIENCE
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