Speeding up In order to speed up on a swing you pump your legs. This probably came natural to you as a child when you first got on a swing and had no one to push you but the physics behind it is very simple. Basically, as you are swinging when you pump your legs, you are raising your legs above your body's center of mass and therefore rising the swing height.
As you continue to pump your legs, the energy that you burn to do so will increase the swing's potential energy and as you keep going, all that extra height adds up and therefore give you a wider swing arc making you go higher.
The students should place the object on the lowered end of a seesaw and push down on the other end. They should discover that using a lever to raise an object requires less force than directly lifting the object.
Next, challenge students to test, and then answer, why it matters where you sit on the seesaw. What happens if you sit close to the center? Each person has a center of gravity. Try This : Ask students to form pairs and observe one another from the side as each tries to lean forward, keeping their legs straight, and touch the ground in front of his or her toes. Ask them to observe how the body changes to stay in balance — when one part moves forward, another part leans back.
Questions : Ask the students to predict answers for the following questions, then test their answers: What would happen if you tried to touch your toes with your heels pressed against the wall? Have students try it against the wall of the school. Is it impossible? What if two students leaned against each other? Now ask your students to design the best ride ever! Challenge the students to choose one piece of playground equipment and brainstorm ways to improve it or invent an entirely new piece of equipment.
Invite students to sketch their designs on paper, adding descriptions of what each invention does and explaining why it is the best ride ever. Remind students to use as many physics words in their descriptions as possible! Create a List. List Name Save. Rename this List. Rename this list. List Name Delete from selected List.
Save to. Save to:. Save Create a List. Create a list. Save Back. Physics on the Playground By Nancy Finton. Grades 3—5. Swinging Forces Materials Needed: Access to at least one swing Plain, white paper, one piece per student Pencils, pens, or markers Science Concept : What makes a swing swing?
Are the periods consistent for each pendulum or do they vary a lot? How different are the two periods? Is this what you expected? What is the total time that each pendulum swings? Do mass or initial angle affect the period of the pendulum? Do they affect the pendulum's total time?
Observations and results Did the longer pendulum have a longer period than the shorter pendulum? Was the longer pendulum's period not quite twice as long as the shorter pendulum's period? A pendulum's period is related to its length, but the relationship is not linear.
A pendulum that is twice as long as another pendulum does not simply have a period that is also twice as long. The exact periods of your longer and shorter pendulums may be slightly less than 1. Perhaps the most famous pendulum is Foucault's pendulum, which showed the earth's rotation in the mids. One of the first known pendulum uses was in about A.
Today pendulums have many applications, including measuring local gravity and helping guide ships and aircrafts. Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue. See Subscription Options.
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