For a transformer, the turns ratio is 3 and its efficiency is 0.75. The current flowing in the primary coil is 2 A and the voltage applied to it is 100 V. Then the voltage and the current flowing in the secondary coil are respectively.

Options

A. 150 V, 1.5 A
B. 300 V, 0.5 A
C. 300 V, 1.5 A
D. 150 V, 0.5 A

Answer

B

Explanation

Here, `(N_(S))/(N_(P))= 3, eta = 0.75, I_(P) = 2A, V_(P) = 100V`
For a transformer
`(N_(S))/(N_(P)) = (V_(S))/(V_(P0))`
`:. V_(s) = (N_(s))/(N_(p)) V_(p) = 3 xx 100V = 300V`
Efficiency of a transformer, `eta = ("Output power")/("Input power") = (V_(s)I_(s))/(V_(p)I_(p))`
`0.75= ((300V) (I_(s)))/((100V)(2A))`
`I_(s) = (1.5)/(3) A = 0.5A`