How does the brightness of a light bulb change in a potential divider circuit?

[lilhaz]

the question reads...
" A 12V battery, of negligible internal resistance is connected to the fixed terminals of a variable potential divider, which has a maximum resistance of 50 ohms. a 12V light bulb is connected between the sliding contact and the negative terminal of the potential divider. sketh the circuit diagram and describe how the brightness of the light bulb changes when the sliding contact is moved from the negative to positive terminal of the potential divider.

any help would be greatly appreciated! :D

 

[vanesch]

Calculate the current through the bulb by solving the circuit...
But there's an element missing: the resistance of the bulb.

 

[turbo]

OK, do you know what the variable potential divider does and how it is hooked up? If you do, you should understand what variable in the circuit will be altered as you slide the contact of the divider. Knowing this, you will know how the potential available to the bulb changes, and what effect this has on the brightness of the bulb. Give it a shot and report back.