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TEJ - Batteries
Volts
The voltage of a battery is clearly labelled and will directly affect the speed of a motor, or brightness of a bulb.
Volts is usually specified just with a V.
5V = 5 volts
Volts is usually specified just with a V.
5V = 5 volts
Amps
The amperage may or may not be listed. The device that you are powering will draw a certain amperage, and the larger the battery is, the larger the device it can supply power to.
1 A = 1 Amp = 1000 mA (milliAmps)
Incidentally, the Arduino can supply 5 volts to an electronic component, but it cannot supply the amps needed to power a motor. Trying this may burn out the Arduino! There are ways that we can get the Arduino to control a motor and we will discuss that later.
1 A = 1 Amp = 1000 mA (milliAmps)
Incidentally, the Arduino can supply 5 volts to an electronic component, but it cannot supply the amps needed to power a motor. Trying this may burn out the Arduino! There are ways that we can get the Arduino to control a motor and we will discuss that later.
Multimeter
The multimeter is a valuable tool to measure volts, amps and resistance. When using the one in TinkerCAD, remember to select the A, V, or R according to what you need to find.
Parallel Batteries
Batteries that are wired in parallel have wires that fork (split into a Y). They will maintain the same voltage as a single battery, but can supply double the amperage which means that the circuit can run twice as long. This will not be used for any circuits in the course, but you should understand the concept.
Each battery on the right is 1.5V. Even though there are 2 batteries, the voltage remains 1.5V because they are wired in parallel. |
Series Batteries
Batteries that are chained together heel-to-toe are said to be wired in series. Their voltages will accumulate, but the amperage will remain unchanged. Batteries that are wired in series don't have wires that fork (split into a Y).
Note: The RED terminal of one battery is connected to the BLACK terminal of the next battery. Each battery is 1.5V and so the total of 3 batteries is 4.5V. A green wire is used to show a connection between red and black terminals. |
Switching Voltage
A switch is not just used to turn a circuit on, or select between two components like a chess clock. A switch can be used to select the number of batteries in a series to change voltage.
In the circuit on the right, the motor has a switch that will select between 1 battery (1.5V) or 2 batteries (3V) which will affect the speed. How does it work? Regardless of the number of batteries used, the common part is that the motor always needs to be connected. So the common of the switch (middle terminal) is wired to the motor. The throws of the switch are wired to the red terminals of two different batteries. The left throw will send 1.5V to the motor but the right throw will collectively send 3V to the motor. |