A transformer has efficiency of $80 \%$. It is connected to a power of 5 kW and 200 V . If the secon

Question

A transformer has efficiency of $80 \%$. It is connected to a power of 5 kW and 200 V . If the secondary voltage is 250 V , the primary and secondary current are respectively\

Professor PC Thomas Classes · Answer

Efficiency $=\frac{	ext { output power }}{	ext { input power }}$ Input power $o=5000 \mathrm{~W}$, input voltage $=200 \mathrm{~V}$\ $	herefore$ Primary current (input current)\ $\mathrm{I}_{\mathrm{P}}=\frac{5000}{200}=25 \mathrm{~A}$\ Out0put power $=5000 	imes \frac{80}{100}=4000 \mathrm{~W}$\ Output voltage $=250 \mathrm{~V}$\ Secondary current (output current)\ $\mathrm{I}_{\mathrm{s}}=4000 / 250=16 \mathrm{~A}$\ $\mathrm{I}_{\mathrm{P}}=25 \mathrm{~A}, \mathrm{I}_{\mathrm{s}}=16 \mathrm{~A}$\