Question

An 1800 W arc welder is connected to a 660 V rms ac line. Calculate (a) the peak voltage, (b) the peak current, and (c) the resistance of the welder. Show all work. Thank you! P.S-Don

Answer 1

a ) peak voltate is V_0 = V_rms * √ 2

                                     = 660 V * √2

                                      = 933.2 V

b) P = i V

     1800 W = i _rms * V_rms

                  = i _rms * 660 V

     i_rms = 2.72 A

I_0 = 2.72 A * √2

        = 3.85 A

c ) Resistance R = V / i

                          = 933.2 V / 3.85 A

                           = 242 ohms