Question

In a step-up transformer, the relation between the number of turns in primary ${\mathrm{N}}_{\mathrm{P}}$ and the number of turns in secondary ${\mathrm{N}}_S$ coils is

• A. ${\mathrm{N}}_S$ is greater than ${\mathrm{N}}_{\mathrm{P}}$
• B. ${\mathrm{N}}_{\mathrm{P}}$ is greater than ${\mathrm{N}}_S$
• C. ${\mathrm{N}}_S$ is equal to ${\mathrm{N}}_{\mathrm{P}}$
• D. ${\mathrm{N}}_{\mathrm{P}}=2{\mathrm{N}}_{\mathrm{S}}$

Answer 1

The correct option is A

${\mathrm{N}}_S$ is greater than ${\mathrm{N}}_{\mathrm{P}}$

Explanation for the correct option:

Option A:

1. In a step-up transformer, the secondary voltage is greater than the primary voltage.
2. Hence, the number of turns in the primary coil will be lesser than the number of turns in the secondary coil.
3. That is, ${\mathrm{N}}_S$ is greater than ${\mathrm{N}}_{\mathrm{P}}$

Option A is correct

Explanation for the incorrect option:

Option B:

Since ${\mathrm{N}}_S$ is greater than ${\mathrm{N}}_{\mathrm{P}}$, ${\mathrm{N}}_{\mathrm{P}}$ cannot be greater than ${\mathrm{N}}_S$

Option B is incorrect

Option C:

Since ${\mathrm{N}}_S$ is greater than ${\mathrm{N}}_{\mathrm{P}}$, ${\mathrm{N}}_{\mathrm{P}}$ cannot be equal to ${\mathrm{N}}_S$

Option C is incorrect

Option D:

Since ${\mathrm{N}}_S$ is greater than ${\mathrm{N}}_{\mathrm{P}}$, ${\mathrm{N}}_{\mathrm{P}}$ cannot be equal to $2{\mathrm{N}}_S$

Option D is incorrect

Therefore, Option A is correct.