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# Spout battery configuration and polarization

Created by Karl Wendt.

## Want to join the conversation?

• why is there only one battery in the place where we put 2 battery?
• There are 2 batteries because in the following videos, he's going to use a trick.

The trick is this: these motors will change the direction of their spin based on which way the electricity flows. He's got the 2 batteries facing opposite directions, and when he wants the robot to go forward, he'll make 1 battery power the motors. When he wants the motors to go backwards, he'll use the other battery (which is sending electricity in the opposite direction).
• Can you tell me in which way the current is flowing and how can we use the right hand rule to understand the direction of rotation in the motors for both the cases?
• What if the batteries don't have enough volts to power the motors?
• What if I used both the batteries?
• Good question, I would suggest testing it yourself
• Can anyone just show me a drawn circuit for the video shown above(Both Cases)
It will be a great help
• What is the black wire for in the first model? The cables are not shown precisely and I cannot understand which wire goes where.
• Is the switch used an SPDT sliding switch? If not, what type is it?
• Because that is how they designed the powering system.
(1 vote)
• I still don't get this. Can someone help me?
(1 vote)
• did you combined all of them
(1 vote)

## Video 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.