11. (AIEEE 2002)
In a transformer, number of turns in the primary coil are 140 and that in the secondary coil are 280. If current in primary coil is 4 A , then that in the secondary coil is
A. 4A
B. 2A
C. 6A
D. 10A
Correct Option is (B)
N p = 140 , N s = 280 , I p = 4 A , I s = ? For a transformer I s I p = N p N s ⇒ I s 4 = 140 280 ⇒ I s = 2 A