(a) Draw a simple labelled diagram illustrating the principle of a step-down transformer and explain how it works
(b) State three ways by which energy is lost in a transformer and how they can be minimized.
(c) If a transformer is used to light a lamp rated at 60W, 220V from a 4400V a.c. supply, calculate the; (i) ratio of the number of turns of the primary coil to the secondary coil in the transformer (ii) current taken from the main circuit if the efficiency of the transforme is 95%.
Explanation
Video Explanation
No video available
Post your Contribution
Discussions (1)
Number c.
Please I will like a rectification of the answer.
From the answer given,
Es = 4400v
Ep = 220v.
This is wrong as main ac supply voltage refers to Ep not Es.
Therefore the 4400v which is the mains should be assigned to the Ep not the Es.
Es/Ep = Np/Ns .
Es= 220v
Ep = 4400v.
220/4400 = NP/Ns.
Number of turns of primary to secondary therefore becomes 1:20 and not 20:1.
Thank you
