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 »



Hi from Alabama
You created power relay with 2 spoons
That’s insane
This is so cool!
greetings from georgia:)
hi from oregon
The four in the countdown was funny XD
its extremely interesting learning about WD-40 and where it came from\Its origin story. I do wonder though, if the WD-40 creation had started in a later time such as 1990’s+.. Including better tools at that I do believe that it wouldn’t have taken them 40 tries to get that one product. Adding onto that, the lesson in this story was meaningful indeed, “Never give up” seems like such simple words but you always have to remember those “simple words” in situations and In life in general. This was a great live.
how does the bell reset?
thats rly cool!!!
I love watching science live!
Wow, I want to try doing this!
It’s amazing how scientists come up with all these different inventions. Relays are used in many different things.
I like learning how things work
Coooooooooooooooooooooooooooooooooool
This weeks live was amazing
This is so interesting!
This is so much fun to learn!
How much power can you give it
This is amazing!!
Hi from New Jersey
kinda Cool
Dr billings is such a inspiration
whoa that is cool
this is interesting.
Hey, everyone! I’m tuning in from the hospital, but it’s nice to still have Science Live.
Love learning lots of different things during these lives.
Hi
Hi from Missouri
Hi from Ohio
Always love learning stuff!
Love learning each week with Science Live!
That’s awesome!
Love learning amazing things from Science Live!
I love science live! I love the example that he did in area 51!
How can we communicate from space to earth when I can’t even get a signal in the mountains?
What type of aluminum is most efficient when making the mechanism?
That was so funny, “I stand corrected, It no longer calls me sir it calls me conductor! ” Why did he name it a coherer ?
I learned that DNA can be used as a space to store information.
Thank you for science live Dr. Billings!
How does the bell reset?
here again from georgia
Wowww this is cool!
DNA is such an interesting topic to me. These science live topics never seem to disappoint! 🙂
Dr billings is an inspiration
Hi from Indiana
Hi from Florida
Would you ever need to replace the switch?
I know that WD-40 has many uses, but I had no idea that there are over 2000 documented applications.
science live is awesome!
Electricity is super interesting, I love learning about how it actually works and I like how it’s not as simple as most people do.
Amazing show, very entertaining!
Loved the lesson on DNA powder today, I can’t believe someone thought of such an idea!
This ScienceLive was very entertaining to watch, I learned a lot from this; Thank you! 🙂
I really thought the fact about DNA acting as storage but for people was really cool
hello from new jersey! I love science.
Science is amazing!
I love Science Live! Great talk this week!
Enjoying the live!
I love science
This was a great video
these lives get more interesting as time goes on. cant wait to see what the next one is about!
hiii
I always love these lives its so interesting!!
What other materials can you put in the cup
I liked learning about how the bell was made, and the inside looks cool
i love science!
how did the spark cause a radio wave?
How does the energy get through it
I would like to know how the coherers were invented.
Amazing video!
Fun live! -Kaleb
Out of context but I love that 3d LED cube at the back
i am enjoying the video very informative
Who was Thomas Edison’s Mentour
Hi from Nc!
I like how the new strands cannot connect with itself like a magnet does with a another magnet.
Hello!
This weeks lesson is really great!
Hello everyone!
this is cool
that’s crazy
oh my gosh this is cool
It was cool to see how the radio waves can turn on the light!
how is the buzzer thing turning on without battery
Hello! Watching from Connecticut!
what is the best way to generate electricity?
Hello from Dallas, Texas! Dear Roger billings, have you constructed or overseen development for hydrogen cranes, trucks, and jets?
Watching the live!
How did Marconi’s lack of formal scientific education shape his experimental approach and perceived legitimacy within the established scientific community?
love what your doing, I always learn something new with each science live!
Hi from Illinois, very interesting live today!
How many volts of electricity would it take to pass through a insulator?
when i grow up i wanna be like Dr Roger billings
WD-40 has a very unique story.
Hello from NC and love science live!
HI FROM NEW YORK
cool stuff Science!!!!!
Happy wednesday
How much power does it take to ring the bell?
how does it turn off right a away when you tapped the lighter on the glass
Hello
oh cool
The science live is the best
I love this live.
Hello
Fun episode tonight
that’s so cool!
I am so enjoying these Science live .
Is there a other way to make a radio wave than to make a spark?
Can we use this bell as an alarm clock?
Thank you! We love Science Live!!
what other inventions did marconi create
Bring back r-51@ please we miss him so much
who invented the word keystone
I was wondering if we can have a class made to be on Morse code?
Area 51
I wonder if new wires and technology can help with power outages?
How long does it take to make those foil balls?
This is my favorite part of the week!!
Love science live!
Dr Billings what is the earliest form of electricity.
Will you ever come to Texas Dr B?
Hi from Virginia! I love learning new things from science lives!
Considering people have an electromagnetic field, is that the reason humans get shocked due to conductivity?
That WD-40 story was crazy! We use it a lot around the house, outside, or just in general. Never thought it had such a story!
I really appreciate the visual that Roger Billing gives us when explaining hard to understand concepts.
Wow, WD-40 is so interesting! I had no idea it was made from NASA.
Always excited to watch Acellus live, hello from MS!
Hello, from Texas. I know Morse code, I was taught it at the age of 11!
Can you do the experiment with a lemon because my mom won’t let me use a lighter?
I am glad you are in are 51 again with another experiment
Love tuning into science live!
you should do more experiments like you did in area 51
I’m from South Carolina
I liked hearing about WD-40 .
DNA tells a lot, what else can we find out about DNA? Science live is amazing, I’ve learned so many new things every week watching science live. It’s absolutely amazing, I love it.
Why did the LED light turn off when you tapped the glass?
How much WD-40 did it take to cover the NASA rocket?
Who invented the door bell?
I love science!
Hi
Thank you for science live.
Thank you for always doing this!
live from IL! Science is one of my favorites
i love science
Good job
It was realty interesting to hear how WD-40 was made and what its original purpose was.
that’s really cool and fascinating about radio signals
Cheers from Texas!
When was morse code Created?
I enjoy watching the science live show.
Its fun to learn something new especially when people are communicating
Hi from Texas .
Hello from Tennessee!!!
Always learning something new!
What is the best way to generate electricity?
Area 51 rocks
What’s the story on how you got access to Area 51?
How can you do modern day morse code
Interesting episode tonight!
How cool!!
Great content
Love it!
Hello from PA!
very cool episode
area 51! cool 😀
I know that WD-40 is useful, but I didn’t know its history. Great lesson, on how to never give-up… keep trying!
I didn’t know that NASA made WD40.
Hello! From NC!!
woah that looks crazy
This is all cool
I like how the balls of foil make electricity.
I love watching the labs!
its nice to be able to see the comments
hi from Texas
Hi r51
Excited for todays show!