Blocking and Tackling - How the Physics of Football Works. Tackling and blocking runners relies on three important principles of physics: ImpulseConservation of momentumRotational motion When Runner and Tackler Meet When our running back is moving in the open field, he has a momentum of 960 kg-m/s.
To stop him -- change his momentum -- a tackler must apply an impulse in the opposite direction. Impulse is the product of the applied force and the time over which that force is applied. F = impulse/t = (960 kg-m/s)/(0.5 s) = 1921 N = 423 lb Alternatively, if the defensive back increased the time in contact with the running back, he could use less force to stop him. In any collision or tackle in which there is no force other than that created by the collision itself, the total momentum of those involved must be the same before and after the collision -- this is the conservation of momentum. Bouncing Balls: A Lesson Plan that Integrates Technology and Physics. Bouncing Balls Introduction: The following lesson involves generating data from a simple physical science activity and then interpreting this data using a computer spreadsheet and graph.
While the activity as written is appropriate for secondary physical science students or students in the middle grades, it is easily adapted for students in upper elementary grades. A sample of the competency goals met by this activity can be found at the bottom of this page. Materials:One meter stick and one numbered ping pong ball for each group. Engage:The The Bermuda Bouncing Balls Company is in the process of designing a new toy -- a small robotic baseball player that will be able to catch a ping pong ball after it bounces. Explore:Each team is given a ping pong ball and a meter stick and asked to begin to collect data. Other questions that may be asked during the Exploration Phase are: How should the bounce height be measured? Before graphing, you have to ask, what sort of graph suits this data? 22. ENERGY TRANSFER - Whelmers - McREL's Accessible Science Series. Instructions: This activity requires some manual dexterity.
Practice each step before presenting it to students. Hold the ping pong ball chest high and release it. Note how high it bounces. Hold a golf ball chest high and release it. Note how high it bounces. The balls must be dropped vertically, with the ping pong ball directly over the golf ball. Presentation: This activity works best on a concrete or hard tile floor. Before dropping either of the balls, ask students to predict how high each will bounce.
After the initial drop of the ping pong ball, ask students how the ball can be made to bounce higher (throw the ball down, drop it from a higher point, etc.). Suggest to students that you will transfer energy from the golf ball to the ping pong ball. Ask students to explain where the energy came from that caused the ping pong ball to bounce so high. Direct them to make careful observations and measurements as you repeatedly drop both balls. Notes: Stacked Ball Drop - Lessons in Conservation of Energy and Momentum. Video of a three-ball stack drop performed by the incomparable Physics Girl.
Balance a golf ball on top of bouncy ball on top of a basketball. Drop the whole stack. What do you think happens? Collisions and Momentum: Bouncing Balls - Lesson - www.teachengineering.org. Summary As a continuation of the theme of potential and kinetic energy, this lesson introduces the concepts of momentum, elastic and inelastic collisions.
Many sports and games, such as baseball and ping-pong, illustrate the ideas of momentum and collisions. Students explore these concepts by bouncing assorted balls on different surfaces and calculating the momentum for each ball. Engineering Connection Crunch! Educational Standards Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards. All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org). In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.
Next Generation Science Standards: Science. Stacked Ball Drop.