heat input for the manual metal arc welding process

Question

A 900 mm long steel plate is welded by manual metal arc welding process using welding current of 150 A, arc voltage of 20 V and welding speed of 30 mm/min. if the process efficiency of is 0.8 and surface resistance is 36 micro-ohm, the heat input will be                                      

(a) 600 j/mm                        (b) 480 J/min

(c) 146 kJ                             (d) 116 kJ

Answer 1

weldingtime=(weldinglength/weldingspeed)

                =900/5

                =180 sec

heat generated=I^2*R*t*efficiency

                      =150^2*36*10^-6*180*0.8

                      =116.6 joule