Praxis: Tough paper
By Medicine Hat News on October 14, 2017.
I can hardly believe that today is Praxis’ 26th annual Family Science Olympics. Trust me, I have been pulling this event together for a number of years now and I have to say it is my absolute favourite time of the year. There is nothing more exciting than seeing families participate in the hands on science challenges with their families and the looks of awe and amazement on even the tiniest little scientist makes all of the hard work worth it! Please be sure to stop by the college anytime between 10 a.m. and 3 p.m. If you cannot make it, below is a similar activity that we have done in the past for you to enjoy at home. Let’s get started! *Remember to ask an adult before doing this experiment. Materials – Kleenex tissue – empty toilet tissue roll – wooden chop stick – rubber bands – table salt – measuring cup – flat work surface or a table Procedure 1. Take the empty toilet tissue roll and place one layer of Kleenex tissue over the end. 2. Secure the tissue paper in place with a rubber band. 3. Try to poke a hole in the Kleenex tissue using the wooden chopstick. 4. What happens? 5. Replace the kleenex tissue paper on the end of the toilet tissue roll. 6. Measure 125 mL (1/2 cup) salt and pour it into the toilet tissue roll. 7. Pack the salt in tightly by shaking the tube gently. 8. Take the wooden chopstick and try to push through the tissue paper once again. 9. What happens? What is going on? Did you know that I was testing how strong you are in this experiment? Actually, we are testing tensile strength. The first time you pushed the chopstick into the Kleenex tissue paper it should have easily ripped. It seems quite obvious as it is so delicate. But what about the second time? The Kleenex tissue paper did not break? How did it become so strong? It is still the same delicate paper. In this instance, there is strength added to the Kleenex tissue paper by the salt. The thousands of grains of salt you packed into the tube allows for more surface area to distribute the force as you push the wooden chopstick into the Kleenex tissue paper. This spreads out the shock or impact, thus allowing the paper to stay intact. I hope to see you today at the Family Science Olympics so you can enjoy more fun hands on activities with Praxis! Patty Rooks is senior scientific consultant at PRAXIS, “Connecting Science To The Community.” Contact Praxis at praxis@praxismh.ca, http://www.praxismh.ca, Tweet or follow us @PraxisMedHat, or friend us on Facebook. 25-24
