An electric doorbell requires a 12 V 60Hz ac supply
a)What turn ratio is required on a transformer to operate from a 120V 60Hz ac supply?
b)Step-up or step-down?
c)If the transformer is connected the wrong way around the circuit what voltage is supplied to the doorbell?
Vs<Vp ---- step down
The Attempt at a Solution
a) so for this I have the Vs=12V and the Vp=120V... 12V/120V= 0.1 giving a 1:10 ratio
120V is too high for the 12V doorbell so it would need to be connected as a step down and convert its high voltage to a low voltage
b) then that makes this a step-down transformer because Vp is greater than Vs
c) This is the part that confused me a little.. So if it was connected backwards would that turn it into a step-up transformer changing the ratio to 10:1
and then 120*10=1200V supplied to the doorbell? And that would be way to much voltage for the doorbell to handle and damage it?
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