Electromagnetic Induction And Alternating Current Ques 90
90. In the method using the transformers, assume that the ratio of the number of turns in the primary to that in the secondary in the step-up transformer is $1: 10$. If the power to the consumers has to be supplied at $200 \mathrm{~V}$, the ratio of the number of turns in the primary to that in the secondary in the step-down transformer is
(a) $200: 1$
(b) $150: 1$
(c) $100: 1$
(d) $50: 1$
Show Answer
Answer:
Correct Answer: 90.(a)
Solution:
Formula:
- During step-up, $\frac{N_{p}}{N_{s}}=\frac{V_{p}}{V_{s}}$ or $\frac{1}{10}=\frac{4000}{V_{s}}$
or $\quad V_{s}=40000 \mathrm{~V}$
In step down transformer,
$$ \frac{N_{p}}{N_{s}}=\frac{V_{p}}{V_{s}}=\frac{40000}{200}=\frac{200}{1} $$
BETA
