Station 1Erin StubbsHarley Long

What will happen when you drop the spheres?

Hypothesis: If all three balls are dropped from the same height, the superball will bounce the highest.

If soaked in hot water, the happy/sad spheres will bounce higher than when not placed in hot water.

The Experiment

ResultsHeight(in inches) at Room Temperature

Trial 1 Trial 2 Trial 3 Average

Superball 27.6 26.7 27.8 27.4Black Sphere 1 0.75 0.8 1.4 0.98Black Sphere 2 1.0 1.2 1.2 1.13

Height (in inches) when heated in water (71°C)

Trial 1 Trial 2 Trial 3 Change Noticed

Black Sphere 1 7.5 7.5 7.0 Bounced higherBlack Sphere 2 6.8 6.9 7.0

Analysis of Experiment 1 The hypothesis was correct. When the black sphere was

exposed to a beaker of warm water and then retested for bounce height, the height increased. Why? The ball had gravitational energy and thermal energy

after being heated. When the ball was not heated, it only had gravitational energy at the start. In both cases, then energy as it fell was kinetic motion energy.

What type of energy transfer was present? Gravitational Potential energy to kinetic motion energy.

Energy was transferred into sound and thermal energy Can you think of any real world applications?

Experiment 2 – Analyzing the types of EnergyToy CarStarted by:Mechanical energy. The car has a spring inside that absorbs the energy when pressed down.Ended by:Friction. Friction changes the mechanical energy into thermal energy and sound.

BalloonStarted by:Mechanical energy that expands the latex in the balloon giving it potential energy.Ended by:Being let go, allowing air to come out, converting the potential energy into mechanical energy for motion, sound, and thermal energy.

Yo-YoStarted by:Mechanical energy. Needs a force to start motion.Ended by:Lose of energy due to friction.

*Friction also plays a role in the speed and length which the yo-yo travels. The yo-yo does not return back to its original position on the string. Energy efficiency.