Subject: If electricity is transformed into heat what comes out the other side

If energy cannot be created or distroyed and kinetic energy is transformed to 
heat say in a light bulbwhat comes out the other side. My dad says only a 
portion is transformed but that would mean there is resistance in the filiment 
and wouldn't that mean the flow is slowed? Electricity flows at the speed of 
light, So how can it be slowed?

Re: If electricity is transformed into heat what comes out the other side