Articles, Blog

Friction is a Force

November 9, 2019


Hi, I am Jared, welcome to Fun Science
Demos. The big idea today is that friction is a force. And through science
we have discovered that friction happens anytime two things
rub against each other. Friction wants to slow things down. So I
have a really simple setup. I have a cardboard ramp and a plain wooden
block. Why is the block not sliding down the
ramp? The force of gravity wants to pull that
block down the ramp. What is keeping it still? The force of
friction. The force of friction is actually
stronger than the force of gravity. What happens if I increase the force of
gravity? I am going to raise my ramp. What happened was, the force of gravity
became stronger than the force of friction. Friction held the
block in place: gravity was just too strong, and it overcame the friction. Through
science we have discovered that the force of friction is different with different surfaces. I have a wooden
block that is plain and smooth, and the same wooden block, but I have
attached a piece of sandpaper, and then another same wooden block, but I have
wrapped it in aluminum foil. Now, through science we have
discovered that the friction is different on these different surfaces. Let us check it out. I am going to slowly
raise the ramp. Which block do you think will slide
first? Which block do you think will slide last?
Friction. Here we go. Now, the trick to make this work
is, you have to go slowly and steadily. I see some movement. Wow! The aluminum foil slid first. Which do
you think is going to be next? Keep raising the slide higher- the plain block went next. You can even
see the friction in action here, its hanging on, it does not want to move. The sandpaper goes down, look at the-look at
the height of that ramp. Friction in action; science is so cool. Friction is all around us, not just on
sliding boards. Take a look at this. I have two pieces of
plastic, I am going to try and spin both of them. Why did it stop spinning? Well,
the friction slowed the block down and stopped it from
spinning. Check it out, same block. Why did it spin so much longer? Well, so how did we cut down the friction? Well,
little glass marbles. The little glass marbles reduce the
friction. Believe it or not, it is a lot like your bicycle wheel or
your skateboard wheel, or even a car tire. They do not have little glass balls in
them, they are actually little metal balls call bearings and you can not always see them
because they are packaged up so they do not rust. Nothing happens to them, but it is meant
to reduce the friction so your tire spins more easily. Friction is a force.
Thanks for watching. Do not forget to check out our links in our video
description.

17 Comments

  • Reply Sylvia Tropp March 8, 2017 at 6:12 pm

    My students love your videos!

  • Reply II MakoShark August 27, 2017 at 4:05 am

    cool video

  • Reply Steritusk's Stuff November 1, 2017 at 10:14 pm

    Hello classmates that look in the comments this is Cole

  • Reply M and A November 9, 2017 at 1:04 am

    I failed my science test I got a 60 ):

  • Reply Pinaki Pandit March 31, 2018 at 8:23 am

    You have so good videos that I every time get question which video should I watch

  • Reply Anil Sharma August 7, 2018 at 5:31 pm

    when the body is at rest ,n no applied force is there then what is the value of friction.

  • Reply Anil Sharma August 7, 2018 at 5:31 pm

    when the body is at rest ,n no applied force is there then what is the value of friction.

  • Reply Noah McGennan September 4, 2018 at 2:35 am

    hi your jared

  • Reply Noah McGennan September 4, 2018 at 2:36 am

    yo

  • Reply Noah McGennan September 4, 2018 at 2:36 am

    im at school

  • Reply Vadim Uritsky September 6, 2018 at 6:38 pm

    I am a physics prof and wanted to clarify one thing. The force of gravity acting on the wooden block IS NOT getting stronger when the surface is tilted. Strictly speaking, it is getting a little WEAKER because the block is moved away from Earth (remember Fg=G m1m2/r^2?), although this change is tiny an can be completely ignored.What IS, indeed, BECOMING LARGER on a steeper slope is the projection of the gravity force onto the slope. The projection is zero for a horizontal surface and it grows with the tilt angle, eventually exceeding the static friction force. It is then that the sliding motion begins.

  • Reply Abdul Khan November 7, 2018 at 1:33 am

    You are very s and smart

  • Reply Anthony Markos November 22, 2018 at 3:49 am

    so good bro

  • Reply Earlyroki February 20, 2019 at 3:31 am

    May the force be with you

  • Reply Kitten Moon February 24, 2019 at 7:43 am

    I like it I will subscribe you

  • Reply hey you April 21, 2019 at 6:34 pm

    OMG THANK YOU SO MUCH, YOU JUST SAVED MY FUTURE

  • Reply Learning is fun with Monalisha Tyagi May 24, 2019 at 4:28 pm

    I like u very much bd ur videos….. u r an inspiration to me….. it would be my pleasure if u see my channels video…. sending u one like… https://youtu.be/43-ZZAjoiYY

  • Leave a Reply