In the transformer shown in the figure below, the load resistance RL is 49.0 . T
ID: 1289318 • Letter: I
Question
In the transformer shown in the figure below, the load resistance RL is 49.0 . The turns ratio N1/N2 is 2.40, and the rms source voltage is Vs = 87.0 V. If a voltmeter across the load resistance measures an rms voltage of 24.0 V, what is the source resistance Rs?
In the transformer shown in the figure below, the load resistance RL is 49.0 . The turns ratio N1/N2 is 2.40, and the rms source voltage is Vs = 87.0 V. If a voltmeter across the load resistance measures an rms voltage of 24.0 V, what is the source resistance Rs?Explanation / Answer
Apply in a transforner Ns/Np = Vs/Vp = Ip/Is
where NS ans Np are seconda dr and primary tunrs
Vs and Vp are secondary and primary volatges
Is and Ip are secondary and prianry currents
also in ideal tansformer output P = input P
out put Power = V^2/.R =24*24/49
P2 = p1 = 11.75 watts
so p1 = Vs^2 /Rs
Rs = 87*87/11.75
Rs = 644.17 ohms