Question 11

 (a) Define:

(i) reactance;

(ii) impedance in an a.c.

The diagram here illustrates an a.c. generator. When the coil is rotated, an e.m.f is induced in the coil.

(i) Explain why an e.m.f. is induced.

(ii) State the purpose of the slip-rings.

(iii) Name and state the law used to determine the direction of the induced current.

(iv) State two ways to increase the induced e.m.f.

 

(c) A lamp is rated 12 V. 6 W. Calculate the amount of energy transformed by the lamp in 5 minutes.

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Theory

Question details

Exam body
WAEC
Subject
Physics
Year
2018
Question no.
#11
Type
Theory

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