Question 5A student in a laboratory wants to light a bulb of 6 W, 11 V rating with a supply of 220 V. Mention the kind of transformer he should use. Also, calculate the turn ratio for the transformer recommended by you.

Question

Accepted Answer

Since the supply voltage (220 V) is much higher than the required voltage (11 V), the student needs a step down transformer to reduce the voltage.

Given,

E_p = 220 V

E_s = 11 V

Let number of turns at primary coil be N_p and at secondary be N_s respectively.

Now,

Turn Ratio = $\dfrac{N_s}{N_p}=\dfrac{E_s}{E_p}=\dfrac{11}{220}=\dfrac{1}{20}$

Hence, recommended turn ratio should be $\dfrac{1}{20}$

Electro-magnetism — Question 5

Question 5