So when I connect the 100Ω lamp, the secondary power is 100W. Then the primary power Pp=Ps/η=100W/50%=200W. Therefore, the current on the primary side will be reduced to I=P/V=200W/200V=1 A. Am I correct?
Homework Statement
A transformer has 400 primary coils and 200 secondary coils. The primary voltage is 200 V, and the current is 2 A. A lamp is connected to the secondary coil. The efficiency of this transformer is 50%. Find the resistance of the lamp.
Homework Equations
V=IR
η=P in / P out...