A small transformer used in a foundry has 550 primary turns and 20 secondary turns. Initially, the switch on the secondary side of the transformer is open, so there is no connection between the two ends of secondary coil.(a) What is the voltage difference between the two ends of the secondary coil, Vs, if a direct current potential of Vp 120 V is placed across the primary coil? (That is, the frequency of oscillation on the primary is zero.) (b) What is the voltage difference between the two ends of the secondary coil, Vs if Vp is 120 V and the frequency of oscillation on the primary is 60Hz? (c) Now equipment powered by the transformer is put into use and the switch is closed. A resistance of 14 Ω is placed between the two ends of the secondary coils. What is the current through the secondary coil? (d) What is the current through the primary side of the coil with the switch closed? Thanks so much!!
A. Zero, since dc current does not have a varying magnetis field. B. 550/120 20/ X 4.3636volts Ne /E p Ns / E s C.4.3636v / 14 .311 a. Es / R t A s D. .011 amp if the transformer is 100% efficient
