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Fun in the Sky:

1. Mass:

Mass would not affect the swing set because swing sets are likependulum, in which Potential Energy (starting point) will be

transformed into Kinetic Energy repeatedly. As we learned PE = KE and

basing it on the formulas:

Since Mass is present in both formulas, it can be cancelled out

therefore proving that mass does not influence the rate of the swing.

m x g x h = mv2

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** The mass of the bob does not affect the period of a pendulumbecause (as Galileo discovered and Newton explained), the mass ofthe bob is being accelerated toward the ground at a constant rate the gravitational constant, g. Just as objects with different masses but

similar shapes fall at the same rate (for example, a ping-pong balland a golf ball, or a grape and a large ball bearing), the pendulum ispulled downward at the same rate no matter how much the bobweighs.

** additional explanation

2. Angle:

Higher Angle:High Potential Energy = Faster Kinetic Energy although it would

move faster as a result of higher angle, the swing would also need to

travel farther distance. Therefore, it would even out a swing with

lower angle.

PE = KE

m x g x h = mv2

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Lower Angle:

Low Potential Energy = Slower Kinetic Energy as it moves slower

compared with a higher angle, the swing would also need to travel

shorter distance. Therefore, it would still have the same rate as the one

with a higher angle.

** the angle that the pendulum swings through (a big swing or asmall swing) does not affect the period of the pendulum becausependulums swinging through a larger angle accelerate more thanpendulums swinging through a small angle. This is because of theway objects fall; when something is falling, it keeps accelerating. Aslong as an object is not going as fast as it can, it is speeding up.Therefore, something that has been falling longer will be going fasterthan something that has just been released. A pendulum swinging

through a large angle is being pulled down by gravity for a longer partof its swing than a pendulum swinging through a small angle, so itspeeds up more, covering the larger distance of its big swing in thesame amount of time as the pendulum swinging through a smallangle covers its shorter distance traveled.

3. Length:

The length of the pendulum determines the length of the pendulum s path during its swing.

Therefore, the length of a pendulum while keeping other factors constant changesthe swing rate of the pendulum. Longer pendulums swing with a lower velocity than

shorter pendulums and they also have to cover longer distance, thus having a longer

swing rates.

** When a pendulum's string is shorter, the pendulum must travel with a highervelocity but with shorter distance. A pendulum on a short string swings fasterthan a pendulum on a long string for the same reason that an ice skater spinsfaster when the skater pulls his/her arms in close to his/her body