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 »
Hello from Kentucky!!
hi from Reno
Hi!
I’m excited to see what r 51 has for us today
hello from Hattiesburg Ms
Hello from Ohio!
hello from nj!
Hi Alyna from texas
Here from Texas!
hello
hello
Hi science live!
hi from texas
Hello 👋
Hi! From New York, I am so excited.
hi!
Hello from Virginia!
Hello! Happy Wednesday!
Hello from WI! Here’s to another great Wednesday night live!
science live is so cool
HI
Hello from texas
Hello! From Maryland
How has been everyone’s day??
hi from Ohio
Hi from Georgia!
Excited for this week’s episode.
Haii!
Hello!!
Here from Colorado
Comment Hello From Las Vegas
Comment Yay! Science!
Jay in the house! 😀
Hi from Nebraska.
hello from nevada
Hello!
Hello from missouri!
Hellooo from kentucky 😀
Hello
Hello from Wisconsin
Comment Good Night from the Virgin Islands!
hi
hi
Hello from montana!
Hi. I’m Avery. I’m 8
hello
Hello
Hello from Arkansas!
Hello from texas
hey
Happy to watch -from Georgia
hi from New York!
I am enjoying Roger Billings live
hello from ny
im here
Hello from NY
Hi everyone! Excited for todays live.
Hi!!!! from TX I LOVE science live episodes
Hi!!! Camilla from Texas 🙂
hello so excited!
Hello from Long Island
Hi
hello from NC
Hi! From Virginia
Hello from Ga
Hey Yall from Ft. Worth Texas!!!!
Hello 😁👍
Good evening from Ga!!
Hello from Alabama!
Hello!
Hello from NC
Hello from NY!
hello from arizona
Hey from tennesse!!
Hi from minnesota
sending love from TX!!
cant wait for this live
Hi from Florida!
Hi form N.C.
I can’t wait for another amazing live I’m interested in the new things discovered it’s my favorite part of all the lives luke here watching from texas
Listening from NC.
Heyyyy watching from Chicago and my birthday is Sunday !
Omg im watching from Chicago too! Also happy early bday have a wonderful dayyyy!!!<3
Hey y’all from TX
I’m ready for today’s live!
HI FROM WA
Hi from Georgia, excited for the new live!!!!!
Hi signing in from kc!!!😁😁
Hi from VA
lets get startd
Hello from Iowa! Have a great day
Hello from MS
Hey from Georgia!!!!!
Hello!
cant wait for next live!
Hi from Denver Colorado
Hello from Tennessee.
Coming from Texas ! Excited to see todays live
Hi from Alabama!
hi everyone!!!
Joining from SC!!!
hi everyone
I can not wait to watch Science Live. Hi from Centerline Rd.
I’m happy to watch cool and stuff to see what yall do next.
Hello from texas
I can’t wait until it starts! watching Live from CT
hello from minnesota my name is elli
Every week has just been banger after banger, keep it coming
I’m here and ready to be educated
Hello from Nebraska
Super cool. :O
hi from louisiana
Hello from Delaware
happy holidays from ms twin
hi from Tennessee!! 😀
Hello From Indinopiolis
Hello from Connecticut!
Love science live wednesdays!!!
Hi, From MN
Hello
Aloha from maryland
my birthday is tomorrow and i am from clarksville!
Oh happy birthday I hope you have a good birthday
Hello from Mississippi
hello from TX
Science Live is my favorite
Hello from Illinois
Hello from Ga!
hi from Georgia
That’s cool I’m going to be going there soon
Hi Zoey!
Hello people from all over the world
Hello everyone ! from texas!
Hello
Hello everyone
Hello from Texas!
Hello from Alabama
Happy Holidays! I can’t wait for this episode! 💜
Hello from CT
hi
hi everyone let have a goood time
Hello I am Justus and I can’t wait for science live.
Hello from oklahoma
HELLO from IL
Wassup from VA 🙂
I can’t wait until SCIENCE LIVE starts 🤩🤩.
Hola from TX 🙂
Hello from Illinois, happy early Xmas!
hey from IL
Hi from Nd !
Hello from Nevada!
science is so fun
Hello for Tennessee.
I am from Rockwood TN!
Can’t wait!
Hello from Illinois! Excited to see what’s in this live today!!
hello from MI!
Hello from North Carolina! I’m looking forward to today’s episode!
I love science live
hello from Hanoi, Vietnam
hello from Oregon
Hi Mia from texas
Hi I’m from San Antonio, TX
Hi from Ohio!
woww!!
watching from maryland
Can’t wait for R-51
hi from wisconsin
hello signing in from tx hope everyone’s day has been fantastic!
Hey from North Carolina
Wassup from Tennessee!
Does anybody else think the monerators are just like, *click, click, click, click!*
Thanks monerators!
Hi from Tx
hi early from Ny
So excited for the live tonight!!!
Hello from Missouri
hi from kentucky
Ready for today’s Science Live!
Hi Zofia!
Hello from Phuket! I can’t wait to watch this livestream.
hi from Illinois
How is everyone doing tonight? Or today wherever you are XD!
I’m Good.
Here watching from texas
hello from Alaska
Hi from California SD
Hii!! From ga
Hello from New Jersey
Mayfield from Calumet City
Hello from Georgia! Looking forward for today’s episode! 🙂
Hello from Alabama
Cant wait for this live
good evening!!
Hi from TX! 🙂
Hello!
yooooo from mississippi
Hi! I can’t wait for the live!!