When you go to the shop, you will buy component called potenciometer, usualy small one with 3 pins.
You can connect it in two styles :
like a rheostat : connect only 2 pins = used for curent regulator
like a potenciometer : connect all 3 pins = used for voltage divider
Potenciometer in the previous connection is connected like reostat. But with the second rezistor this thing works like potenciometer, so divides voltage... very simple.
Of course, its possible to buy potenciometers for higer wattages = usualy used like rheostat, so the third pin is "not connected". This high wattage potenciometer in volt divider is for nothing.
You can connect it in two styles :
like a rheostat : connect only 2 pins = used for curent regulator
like a potenciometer : connect all 3 pins = used for voltage divider
Potenciometer in the previous connection is connected like reostat. But with the second rezistor this thing works like potenciometer, so divides voltage... very simple.
Of course, its possible to buy potenciometers for higer wattages = usualy used like rheostat, so the third pin is "not connected". This high wattage potenciometer in volt divider is for nothing.