Spout battery configuration and polarization
About this video
A mock-up circuit with two motors and a battery shows how the direction of a motor depends on the direction of current. With the battery connected one way, both motors spin one direction. Flipping the battery's orientation reverses the flow of electricity through the motors, so they spin the other way. The positive wire is tied off because the single 1.5 volt battery is enough to drive both motors.
You'll be able to
- trace the path of current from a battery through a switch and two motors.
- predict how reversing the battery's orientation changes the direction a motor turns.
- explain why reversing the flow of electricity changes the direction of motor movement.
Key words
- Mock-up
- A physical model of a circuit built to show how its parts connect and behave.
- Motor direction
- The way a motor spins, which depends on the direction current flows through it.
- Polarity
- Which terminal of a battery is positive and which is negative, which sets the direction of current.
- Ground wire
- The return path, here the wire from the battery's negative side, that completes the circuit.
Transcript
So this mock-up was created to show another part of the circuit. When we turn the switch here, the power switch, we see both the motors spin in this direction. They're pulling power from the battery, and it's flowing through the motors causing it to spin this way.
So you can see that the ground wire from the battery here is connected to the blue wire, which goes to the motors. And then that goes to a switch, and that's connected back to the positive side on the battery here. So that's causing the motors to spin in this direction when they're wired like that.
Notice the positive wire here is tied off. We don't need the positive wire, because we're using this yellow wire to connect to the batteries. And we just need this one battery to power these two motors, because one battery is 1.5 volts and that's enough to get the motors to turn.
And so we're going to use this battery to make the motors turn backwards. You can see when we turn it on the motors spin backwards. Now in this configuration what we've done is we've created a mock-up again. And we want to be able to make the motors again spin forward and backwards, so this set-up the motors are spinning forwards.
So you can see they're going like this, they're going forward. And the batteries on the other side, and we're connected to the positive wire instead of the negative wire, and again the negative wire is being taken care of because this wire is coming through here.
So what we've done is we've changed the orientation of the battery. And so the power is flowing the other direction, causing the motors to go forward. So if you reverse the flow of electricity, you can change the direction of the motor movement.
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