1. The problem statement, all variables and given/known data A step down transformer produces a voltage of 6.0 V across the secondary coil when the voltage across the primary coil is 120 V. What voltage appears across the primary coil of this transormer if 120 V is applied to the secondary coil? 2. Relevant equations Vp/Vs=Np/Ns=Is/Ip ................. ???? (not sure if that is relevant really) 3. The attempt at a solution i know Vs/Vp = 120/6 i think i dont really know what to do with the 120 v applied to the secondary coil i added 120 to the 6 = 126 that means 6 was multiplied by a factor of 21 so i multiplied the top value of the ratio (120) by 21 and got 2520 v but im really not sure if thats right at all? what does "120 V is applied" in mathematical terms?