Posts Tagged ‘friction’

Warming Things Up with Friction

Monday, September 26th, 2016


Today we will be warming things up with friction. We will be rubbing coins against the carpet to see if they get hot. We will be using an infrared camera to see how hot the coin gets after experiencing friction.

Next we will rub our hands together. You will see that the ring on my husband’s hand does not get hot, probably because the ring is tight on my husband’s hand, so the ring got no friction when he rubbed his hands together.

The grand finale is the vacuum cleaner. You will have to watch the video to see how the vacuum cleaner creates a line of heat in its path!

Heat & Friction Experiment: Infrared Camera (video)

This post contains affiliate links. I was compensated for my work in writing this post.

This experiment is from Christian Kids Explore Physics by Bright Ideas Press. We have been enjoying all the hands-on activities that bring the subject of physics to life for kids.

Coin Friction Experiment

Hold a coin against your cheek and see how cold it is. Now rub it against the carpet for 30 seconds. Low-pile carpet works better than shaggy carpet, by the way. Then place the coin against your cheek again and notice the difference in temperature of the coin.

Try different coins: penny, nickel, dime, and quarter. Rub harder or faster and see if the coin gets hot faster.


We measured the temperature of the coins before and after rubbing them against the carpet. We saw an immediate change in temperature, even to the carpet underneath it! We could sign our name in the carpet with the coin, leaving a hot trail on the carpet. This reminds me of signing my name with sparklers on New Year’s Eve.


Hand Friction Experiment

My daughter rubbed her hands together, and they got hotter. This is why if you are out in the snow and you are super cold, you can feel warmer when you rub your hands together, because the friction creates warmth.


I hope you enjoyed this fun heat and friction experiment. I had to laugh when I saw what my face looked like with the infrared camera!

Changing the Coefficient of Friction

Monday, August 15th, 2016


Today we are doing an experiment about changing the coefficient of friction. We will be swooshing a penny and a book across an unpolished table. Then we will polish the table and try it again.

Friction is resistance that keeps an object from moving forward. As you can see in the video, our coffee table has seen better days–it is battered and has lots of tiny grooves and dents. This provides a surface that is full of friction to cause a penny or book to slow down while being slid across a table.

How to do the friction experiment:

sliding-pennyThis post contains affiliate links. I was compensated for my work in writing this post.

This is how we conducted this friction experiment from Christian Kids Explore Physics by Bright Ideas Press:

Step 1: We slid a penny and a book across an unpolished table. We noticed that the penny got stuck as it didn’t want to slide across a table full of nicks and dings.

Step 2: We polished the table with furniture polish. Using a soft rag worked better than using a paper towel, as far as shining the table. The reason the table never looked visibly shiny is that there was no varnish left on the poor coffee table. Even then, the table became more slippery when polished.


Step 3: We slid the penny and the book across the polished table. This time we noticed that the penny had less friction as it slid across because there were fewer obstacles slowing it down.

My kids went next door to slide the penny on the neighbor’s waxed wooden floor. The penny slid around with way more speed! Even the neighbor’s dog had trouble walking on such a frictionless surface!

Then my husband polished one side of the coffee table and not the other, and there was a visible difference in speed when he flicked two wooden coins across the table. The polished side went noticeably faster and flew off the table!