KCET2007PhysicsAlternating Current
A step-down transformer reduces the voltage of a transmission line from 2200 ~V to 220 ~V . The power delivered by it is 880 ~W and its efficiency is 88 % . The input current is
Options
- A4.65 ~mA
- B0.045 ~A
- C0.45 ~A
- D4.65 ~A
Correct answer
C. 0.45 ~A
Step-by-step solution
Efficiency of transformer, aligned &= Output po Input powe 88 100 &= 880 P_ i P_ i &=1000 ~W Input current, I_ P &= P_ i V_ i &= 1000 2200 &=0.45 ~A aligned