Use the slider to change the voltage of the battery and observe the effect on the current. High voltage is like high pressure in the water flow examples--it causes a high flow rate. Lower pressure results in a lower flow rate.
The greater the current through the light bulb, the brighter it glows.
Now wait a minute! Current is the flow of electrons, which are negative and move from negative to positive. Why does this show little positive charges moving from positive to negative? Isn't that backwards? Well, sort of. Click here for an explanation.