A) 30%
B) 50%
C) 90%
D) 10%
Correct Answer: C
Solution :
The efficiency of transformer \[=\frac{Energy\text{ }obtained\text{ }from\text{ }the\text{ }secondary\text{ }coil}{Energy\text{ }given\text{ }to\text{ }the\text{ }primary\text{ }coil}\] or \[\eta =\frac{Output\,\,power}{Inputpower}\] or \[\eta =\frac{{{V}_{s}}{{I}_{s}}}{{{V}_{P}}{{I}_{P}}}\] Given, \[{{V}_{s}}{{I}_{s}}=100W,\,{{V}_{p}}=220V,\,{{I}_{p}}=0.5A\] Hence- \[\eta =\frac{100}{220\times 0.5}=0.90=90%\] Note The efficiency of an ideal transformer is 1 (or 100%). But in practice due to loss in energy, the efficiency of transformer is always less than 1 (or less than 100%).You need to login to perform this action.
You will be redirected in
3 sec