Voltage and Current
Voltage and Current are the push and flow of electricity — voltage pushes, and current is how much flows.
Two jars sit on a shelf, one higher than the other, linked by a tube. The high jar pushes water down through the tube toward the low jar. That push from the height gap is the voltage. The stream of water flowing through the tube is the current. More height means a stronger push and a faster flow.
Explaining voltage and current by grade level
A solar cell in the sun makes power move through a wire. The push that sends power out of the cell is like water pressure in a hose. The flow of power through the wire is like the water streaming out. More push and more flow mean more power to use.
Projects that explore voltage and current
A solar cell generates both voltage — the push that drives electricity — and current, the amount that flows. You can measure both: voltage in millivolts, current in milliamps, and calculate power in watts. Temperature affects how much the cell generates, with higher temperatures tending to reduce both readings.
Tilting a solar cell changes both the push and the flow of electricity it produces. You mount the cell on a board, move the board to different angles with the sun, and measure the voltage going to the cell at each position. When the cell sits perpendicular to the sun's rays, the power going to the cell is maximized.
Concentrating more sunlight onto a solar cell raises both the push and flow of electricity it produces. You measure the voltage and current with no reflector, then with a flat mirror, then with an aluminum-covered parabolic dish. The parabolic reflector produces the highest power output, followed by the flat mirror.
Voltage pushes electricity through a solar cell, and current is how much flows. Both depend on the angle of incoming sunlight. You measure the voltage and current from each cell at angles ranging from perpendicular to nearly flat.
Voltage provides the electrical push, and current determines how much electricity flows through a circuit. Temperature affects both values in a solar cell. You measure each cell's voltage and current after exposing three identical solar cells to different heat conditions to see how temperature shifts the push and flow of electricity.