In the rope loop, you running down and the warming are equal. You don't get something for nothing, and you don't do something for no reward either.
running down = flow × pull
warming = flow × pull
running down = warming
In the electrical loop, the battery running down and the glowing are equal. You don't get something for nothing, and you don't get nothing for something either.
running down = current × voltage
glowing = current × voltage
running down = glowing
How much running down, glowing and warming are all examples of how much power
. The power is a number of watts. This number you'll find on many light bulbs in shops, where watts
is shortened to W
; 6 W, 60 W, 100 W. You'll also find watts on kettles, microwaves, and many other things around the home.