The Relay
December 10, 2025 • EPISODE 290
How does a simple relay help us understand electricity and circuits? In this episode of Science LIVE, Roger Billings breaks down the science behind the relay—the clever electromagnetic switch that makes it possible to control circuits with precision. Learn how relays work, why they’re essential in everyday electronics, and how this simple idea became a building block for modern technology. A clear, hands-on look at one of engineering’s most important tools.

About DrB
Dr. Roger Billings is a visionary innovator whose work has touched the lives of millions of students and transformed the landscape of education. Widely known as “DrB” to the countless kids who benefit from his groundbreaking Acellus learning system, Dr. Billings has dedicated his life to advancing education through technology.
As part of DrB’s lifelong commitment to supporting education, Science LIVE was launched as a way to “give back” by mentoring students in conjunction with the Roger Billings Scholarship Program.
Read more about DrB »
About the Roger Billings Scholarship Program »



My Dad uses WD-40 all over the house for things and my bike!
Comment* how many times did NASA want to give up on there inventions when they weren’t working like they wanted it too?
How many times did the WD40 company fail before they figured out something that could be used world wide?
Amazing video
hello from georgia
WD-40 has a very interesting story!
Hello from Maci
Can WD-40 remove paint stains?
I think I’ve been inspired to keep trying
I never knew that there were so many uses for WD 40
WD 40 yay
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What if you use copper on the rocket as the shell to help cool it down?
What other odd uses is WD 40 used for?
I wonder how hard it is to make stuff like that.
hello from OH. Loving science live
i didn’t know there were that many uses for WD-40
My mom is impressed with the WD-40 story. She didn’t know about it.
WD 40 is a great product.
My Dad uses WD-40 on everything!!!
I think it’s so neat that from Nasa, there is 2,000 uses for WD40. Just Wow!
Hello from Maryland! I saw someone in the comments is from Brazil! Crazy how we go to the same school and we are no where near each other.
The science lives are always so interesting! Happy to be here!
my dad loves wd40
So excited for science live again. I look forward to learning something new every week.
I am going to have to look up all those uses! I had no idea!
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Hello from NY! My mom said she loves WD 40-it works amazing!
My dad uses wd40!
I see a lot of people from Texas. Hello neighbors!
I 💕 Science Live Dr.B 🧓
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This just shows that no matter what you should keep trying!!!
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I love science live I look forward to it each week because I get to learn new things.
my dad loves WD-40!
Rust is oxodized Metal! Yep, I’m a Chemistery Geek!! 😀
My name hast be Luke and I hail from over yonder in the great province of Georgia. I must thank thee Lord Billings that thou takes thy valuable time each Wednesday to teach myself and mine peers of the great and broad fields of Science.
My dad uses WD-40 all the time! I never knew how it was made!
Always wondered about the reason behind the 40 in WD-40. Very interesting.
My dad uses WD-40.
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I’m here from Port Angeles!
My dad uses WD-40 a lot.
Hey from Florida, I thought the process of rusting was cool.
My dad uses that spray.
My Dad says every toolbox should have duct tape and WD-40!
hey from Texas
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hello from Mississippi
can you use the formula on cars to make them not rust also merry Christmas to everyone
Is there water in space?
So that’s what WD40 means haha
Having done a porject regarding the sustainability of rocket flights and expended fuel, this lesson resonated with me.
A formula to keep water off rockets to protect the steel is awesome!
I always look forward to Wednesday’s Science Live.
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How does technology work with DNA? Would that be considered biotechnology or biomedical engineering?
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I don’t really have a question to ask but i just wanted to give insight and say that i really do like science live and i honestly think it’s really cool what scientist can do.
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Does DNA storage resist water and heat.
they failed but they never gave up 👍
The 40th time trying worked!
I LOVE SCIENCEEEEEEEEEEEE
That’s so cool that WD40 can be used for so many things! Its a great invention.
Hi from MA. Thank you for explaining oxidization. I love how you all explain science so well.
What an interesting tie!
Tuning in from Michigan!
how much DNA would you need to get to one Terabyte?
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Hi i hope all of you guys are having a good day or night. Zion from Indianapolis
Does water help other elements, besides steel, form together?
DNA can tell a lot.
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Ready for todays video!
hi I’m just here but I wanna say I love the break through part the most
Wow
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Wow, that is a lot of failed formulas!
Science, it’s pretty cool. I really like these lives.
It’s WD-40!!!
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Comment This is so cool. I to hear about space and rockets and stuff.
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Hello from Kentucky
Can you manually make rust?
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Hi from NJ!!!
what would happen if they didn’t see the rust on the spaceship, what would happen, would it like still fly or would it break?
Science is amazing.
so what did they make for it to work then
Hello from West Virginia!!!!
how are they going to make formula that won’t come in contact with oxygen while coating on the rocket
I love sience, I’ve learned many new things from it
Love these
Just keep trying until you succeed
Hello from Utah, im excited to hear what were talking about today
How is stainless steel different from steel?
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love from tn!
I wonder what their reaction was after the first successful rocket launch
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i want to learn more about DNA
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Hello there!
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im learning so much !! How can you hook DNA into a computer
So interesting!
Wow, rust is actually really interesting
Hello from ILLINOIS people live by me that’s…COOL and those people I might meet someday.
Could they have added something to the steel so it does not mix?
How many years were in between the Atlas mission and Apollo 13 mission?
Hi from G A.
Hi from GA !!!!
How could I use DNA?
So something like oil so that it repels the water
Hi from Argentina.
how thin do they make the layer
Hello from MS!
Hello from NC
Why does oxygen weaken steel via rusting?
i can not wait to learn something new!
I love the Thomas Edison comment. I will always try again. Good reminder to never give up.
Who is your favorite teacher in Acellus?
Hello! From Indiana
Science is cool
what about… Mod Podge?
hi from GA
Hello!
Hello again!
This is really interesting.
I can’t wait to watch it again next week!
TEXAS is best so hello from TEXAS
nice vid
Does DNA storage have temperature requirements
so entertaining
So interesting
Hey Dr. Roger Billings I’m back from Florida!
To Tobia’s Question about how many times I would try to do something Before you give up and I said aloud “A Trillion Times!!!” 😀
Science live is cool
Hello from Cairo!
How much gas does a rocket ship use ?
Rockets are always so interesting, hopefully one day humans can make it into the stars
How did they figure out the heat shielding for the steal?
Wow, that’s a lot of rust!
hi
Watching from Kentucky
SCIENCE LIVE
hiii
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hi
I like science
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hello!!!!!
r.51……..IS…………FUNNY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
thats cool I didn’t know that
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I did not know iron or steel can look like that.
hi from kentucky
What are current rockets shells made of?
hello from Oregon
woah this is so cool!!!
The Data stored by DNA lesson was simply fascinating thank you so much !
wow so interesting
Todays episode has been so informational, I’m really interested in everything being said.
wow
That is pretty impressive!!
hi from cali
Hi from Maryland and just LOVE break through moments with Dr. Tobias!