HARVEYS LAKE — An object at rest stays at rest, Sarah Rowley from the Franklin Institute’s Traveling Science Show told students at Lake-Noxen Elementary School on Friday.
To prove her point, Rowley yanked a piece of silky blue fabric from under a glass bowl on a table without making the bowl move.
The concept was one of several of Sir Isaac Newton’s Laws of Motion that Rowley demonstrated to the school’s kindergarten through sixth-grade classes during an hour-long interactive assembly organized by the parent-teacher organizations from Lake-Noxen and Ross elementary schools.
Rowley conducted her science show for Ross Elementary in the morning and then came to Lake-Noxen Elementary for an afternoon show.
“Let’s start with the first law of motion. That is the law of inertia,” she said. “The law of inertia starts with an object at rest stays at rest. What does at rest mean?”
More than 100 students shouted, “at rest.”
Rowley pointed to the glass bowl on the table and said the bowl is at “rest,” but the blue fabric was not because she pulled it out from under the bowl.
In the example, Rowley said she was the force to make the material move. Force and friction are involved in all movement on earth, she said.
“If I used sandpaper instead of the silky material what would happen to the bowl?” she asked.
“It would move,” the audience answered.
“It would move because of friction between the bowl and the sandpaper,” Rowley said.
Rowley used an orange block of wood with four black plastic wheels on it and a carbon dioxide canister to demonstrate Newton’s second law, involving, force, mass and acceleration.
She attached the CO2 cylinder to the upside down car. Then she poked a hole in the CO2 canister. The block was pushed a short distance on the stage.
Rowley explained the wood’s complete surface sliding on the stage created friction and prevented it from moving too far. But when she turned the block around, so the car rested on its four wheels, and punctured the CO2 cartridge, the car was propelled halfway across the stage.
On its wheels, the block of wood reduced the friction, and the CO2 was the force causing the car to accelerate, she said.
Fourth-grader Arianna Garrett helped demonstrate Newton’s final law, which is for every action there is an equal and opposite reaction.
Garratt stood on a lazy Susan. Rowley handed her a red plastic baseball bat and had her swing. Garrett’s whole body shifted with every swing because the lazy Susan reduced the friction her feet had on stage.