AIIMS2017PhysicsAlternating Current
A transformer with efficiency 80 % works at 4 ~kW and 100 ~V . If the secondary voltage is 200 ~V , then the primary and secondary currents are respectively
Options
- A40 ~A and 16 ~A
- B16 ~A and 40 ~A
- C20 ~A and 40 ~A
- D40 ~A and 20 ~A
Correct answer
A. 40 ~A and 16 ~A
Step-by-step solution
aligned & (a) : Here, =80 % & P_i=4 ~kW =4000 ~W & V_p=100 ~V , V_s=200 ~V & I_p= P_i V_p = 4000 100 =40 ~A & = V_s I_s V_p I_p ; 80 100 = 200 I_s 4000 = I_s 20 & or I_s= 20 80 100 =16 ~A aligned