A heater coil is rated 100w,200v.it is cut into two identical parts.both parts are connected together in parallel to the same source of 200v.calculate the energy liberated per secondin the new combination.

power rating,m P = 100 W

voltage supply, V = 200V

thus resistance of the coil:

P = V² / R

thus R = 40000/100 = 400 ohm

hence of the two new parts produced, new resistance of each part, R' = 200 ohm each

on parallel connection, net resistance:

1/Rt = 1/R' + 1/R'

hence Rt = R'/2 = 100 ohm

and the new power rating, P = V² /Rt = 40000/100 = 400 W