Science Buddies: "Ask an Expert"

Hello, I am making a dancing robot following the instructions. I need to use 3 types of energy for the project. I think I have all 3 already, sound energy since he makes sounds when he moves around the floor, mechanical and electrical. Is it correct?
If I wanted to put small lights on him, what parts should I order? He looks very small and fragile, I don't want to make him too heavy to move. Thank you

Hi vseriaga,

You are correct about the types of energy. Technically you could also say gravitational potential energy because the arms move up and down as it "dances."

If you want to add lights to your robot, you can add LEDs. They are very small and will not add too much weight. For example, something like this:

https://www.sparkfun.com/products/12062

You will also need to include a resistor with your LED to prevent it from burning out. You can learn more about resistors and LEDs in this video:

https://youtu.be/EeCh68a1GEg

For the dancing robot you will need a resistor somewhere in the 100-200 ohm range (the exact value is not critical), like this:

https://www.sparkfun.com/products/14493

Resistors and LEDs are also available on Amazon.com.

If you haven't already, I would highly recommend watching the video in our breadboard tutorial, which will help you figure out how to connect the LEDs:

https://www.sciencebuddies.org/science- ... breadboard

Hope that helps, please write back if you have more questions!

Ben

Are those LEDs from Amazon the same ones as the other ones?

Hi Hildebrander,

Are you referring to the link in the description of the breadboard video on YouTube? If so, that is a search link that shows many types of LEDs, since we're not sure how many people will want to buy. But something like this:

https://www.amazon.com/DiCUNO-450pcs-Co ... 073QMYKDM/

is the same as what I linked from SparkFun above. Note that it is way cheaper per LED to buy them in bulk, but most people probably don't need 450 LEDs!