Therefore, something that has been falling longer will be going faster than something that has just been released. A pendulum swinging through a large angle is being pulled down by gravity for a longer part of its swing than a pendulum swinging through a small angle, so it speeds up more, covering the larger distance of its big swing in the same amount of time as the pendulum swinging through a small angle covers its shorter distance traveled.
Watch this activity on YouTube. Ask the students to explain which factors might affect the period of a pendulum. Answer: Pendulum length, bob weight, angle pendulum swings through. Which factor s really do affect the pendulum's period? Answer: The length of the pendulum. Why does the weight not make a difference? Answer: Because the pendulum, just like falling objects, is not dependent on weight.
How does the length of a pendulum's string affect its period? Answer: A pendulum with a longer string has a longer period, meaning it takes a longer time to complete one back and forth cycle when compared with a pendulum with a shorter string.
Also, the pendulum with the longer string has a lower frequency, which means it completes less back and forth cycles in a given amount of time as compared with a pendulum with a shorter string. Why does the angle the pendulum starts at not affect the period? Answer: Because pendulums that start at a bigger angle have longer to speed up, so they travel faster than pendulums that start at a small angle.
One oscillation is complete when the bob returns to its starting position. Count the votes and write the totals on the board. Give the right answer. Human Matching: On ten pieces of paper, write either the term or the definition of the five vocabulary words. Ask for ten volunteers from the class to come up to the front of the room, and give each person one of the pieces of paper.
One at a time, have each volunteer read what is written on their paper. Have the remainder of the class match term to definition by voting. Have student "terms" stand by their "definitions.
As a library research project, have the students research Galileo Galilei. What other scientific findings did he make during his lifetime? Have the students' research the ways that engineers use pendulums today. Some suggestions: seismographs, inertial dampeners, in sky-scrapers.
Gamow, George. The Great Physicists from Galileo to Einstein. Wolfson, Richard and Jay M. Physics: For Scientists and Engineers. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.
Why Teach Engineering in K? Find more at TeachEngineering. Quick Look. Print this lesson Toggle Dropdown Print lesson and its associated curriculum. Foucault's demonstrations show a pendulum that appears to rotate. Actually, the pendulum set up makes rotation impossible, which means it is the floor beneath the pendulum that rotates. Iam Jaebi has been writing since His short story, "The Alchemist," reached over , readers and his work has appeared online in Thaumotrope and Nanoism.
His novel, "The Guardians," was released in by Imagenat Entertainment. Jaebi is also a business writer specializing in company naming, concept designs and technical writing. He graduated from Syracuse University with a Bachelor of Science in computer engineering. Related Articles History of the Pendulum. How to Calculate Pendulum Force. Mary Abel has been writing poetry since Her poems have appeared in two anthologies published through Poetry.
Abel also wrote and edited for her collegiate poetry publication in Madison, Wis. She received a Bachelor of Arts in education from Edgewood College. Related Articles Facts About Pendulums.
History of the Pendulum. Why Is a Pendulum Scientifically Important? The Use of Pendulums in the Real World. Objects Which Use Pendulum Movement. Different Types of Pendulums. The History of Wind Vanes. Modern Uses of a Catapult. Even though the ride is pulled down by gravity, the inertia of the object pushes the ride right back up into the air, creating a swinging motion. Once the ride is in motion, it stays in motion unless an outside force slows it.
At an amusement park, a ride like this is stopped by brakes, or else it would just keep swinging and you would be riding it long after closing time! To explain the amusement park ride the way we just did, we used the ideas of a pendulum and Newton's first law of motion. A pendulum is a mass called a bob that hangs from the end of a rod or string, and swings back and forth.
Who has heard of a pendulum before? A pendulum is made of an object with a mass, called a bob that dangles from the end of a rod or string and swings freely. The amusement park ride we just talked about is actually a huge pendulum. Can anyone think of another example of a pendulum? Anything that swings under its own weight is a pendulum — a playground swing, a curtain cord or a carpenter's plumb.
Even your own legs behave like pendulums. In fact, the most efficient way to walk is to let your legs swing at their natural rate. The time it takes for your leg to make its back and forth movement depends on the length of your legs. That's why long-legged people sometimes appear to saunter along; short-legged people, to walk briskly.
Some clocks, such as a grandfather clock, have a pendulum that swings to keep track of time. Because pendulums continue to swing without changing their speed unless acted on by an outside force, they can accurately help us measure things like time. The type of pendulum we described with the Sea Dragon ride is known as a simple pendulum , because it only moves back and forth like the swings on a playground swing set.
Another type of pendulum is a spherical pendulum , in which the bob not only moves back and forth, but in a circular motion. Can anyone think of an example of a spherical pendulum? A tether ball moves as a spherical pendulum. Another example is an amusement park ride that spins you in a big circle.
This amusement park ride works like a spherical pendulum. All rights reserved. Why does a pendulum stay in motion? More than years ago, an Englishman named Isaac Newton described the natural behavior of motion and gravity in our world, in what he called the "three universal laws of motion.
So, something that is moving keeps moving until something else stops it. Does this remind you of the Sea Dragon ride? Or, have you ever been able to stop ice skating or roller skating without the help of an outside force perhaps dragging your foot or crashing into someone? Or, how do you stop when you are swinging on a playground swing? Sometimes moving objects seem to stop without the help of an outside force. For example, if you slowly roll a ball across the floor, it eventually stops on its own.
Does that mean Newton's first law of motion does not always hold true? The floor has roughness or friction — a resistance to motion — that slows the ball. In this case, friction is the outside force that stops the ball from rolling. Pendulums work so well because they move through air, which has very little friction. Engineers often incorporate the ideas of the pendulum and Newton's first law of motion when they design things that we use everyday or that help people in some way.
In fact, engineers always must consider the "invisible" natural forces acting on objects in motion, such as inertia, to keep us safe. What are some ways that an engineer might be able to use a pendulum? The continuous swinging of a pendulum keeps time for some clocks. Engineers use pendulums in designing lots of things, from clocks to amusement park rides. Some engineers who study the Earth and earthquakes, design equipment and sensors such as seismometers, which use the idea of a pendulum to measure earthquakes.
Understanding pendulum mathematics helps engineers determine how much swaying back and forth a building can safely withstand during a windstorm or earthquake. If a building might build up too much inertia moving it back and forth, then engineers must figure out ways to safely counteract the movement to protect the people and property.
Real-world applications like these make the pendulum and inertia important concepts for engineers — and you — to understand. To help convey the lesson's content, refer to the associated activity Swinging with Style where students experientially learn about the characteristics of pendulums by riding on playground swings.
Newton's three laws of motion make up the foundation for the known physics of motion. The first law states that an object in motion stays in motion and an object at rest stays at rest, unless acted upon by an outside force. This is the concept of inertia.
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