But how much power do I need?

ONE RULE – never short circuit a battery!  does anyone know what that is?

We have used many different batteries over the past two weeks, but how do you know what battery is right for your project?  The formula that was touched upon last week in the video by Super Awesome Sylvia talked about Ohms Law Voltage=Resistance X Current. Right now we will focus on Voltage, which for our purpose will help us decide what battery we need for our challenges and eventually our project.

Different components use different amounts of Voltage For instance:

LEDs depending on their color use different amounts of Voltage. LED Color Chart and Design Guide.  Sometimes things are labeled and sometimes they are not.  Always start LOW and add more. If you use the wrong size battery your LED will burn out and Never work again.

I buy the LEDs from all different places but most LEDs at GHS follow the following:

3.0-3.4V – Violet
3.0V – 3.4V – Blue
3.0-3.4V – Green
1.8-2.2V – Yellow
1.8 – 2.2V – orange
1.8-2.2 V – Red
3.0-3.4 – Pink
3.0 – 3.4V – White

Motors (found at GHS) 1.5V-5V (motors are more forgiving on Voltage)

What if I don’t have the correct size?  Well you can put two batteries  in series doubling the voltage.  The voltage on the batteries MUST be similar  and have the same Voltage so test with your multi meter.

If I want to light up 2 Green LEDs in series what battery would I use?

Do I have that size?  If not how do I Make one?

ACTIVITY: Completed serial challenges from previous week.

This weeks activity is to complete the following challenge cards BatteriesNotIncluded found on the.

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