## SCIENCE OF NFL FOOTBALL: Newton's 2nd Law of Motion & Kicking (Grades 5-8)

##### Objective:

Objective: Students will be able to understand and discuss Newton’s 2nd Law, force, impulse, and momentum to understand how these concepts apply to sports such as football.

##### Introduction Notes:

**SCIENCE OF NFL FOOTBALL**

**Newton’s 2nd Law of Motion & Kicking (Grades 5-8)**

**STEM Lesson Plan**

**Lesson plans produced by Lessonopoly (lessonopoly.org)**

**Video produced by NBC Learn in partnership with the NFL and the National Science Foundation**

SPECIFIC OBJECTIVES:

Students will be able to: Explain Newton’s 2nd Law, both verbally and mathematically; Explain impulse and momentum; Explain a net force; Analyze forces on an object; Draw force diagrams representing forces on an object; Discuss whether forces on an object are balanced or unbalanced; Use Online Physics Simulation software (PhET); Build and play a game of paper football.

REQUIRED MATERIALS

Computer and internet connection, Scrap paper (for paper football game), Safety goggles

ANTICIPATORY SET (LEAD-IN)

Ask the students to discuss what a force is (a push or a pull). Ask for examples in everyday life. Ask for examples of force in football. Ask if the students have ever kicked a football (or some other type of ball).

What types of forces are pushing on the ball?

What can you do to make the ball go higher or farther?

Tell the students: “Today we will discuss how force affects kicking a football”.

Watch the NBC Learn Science of NFL Football video: “Newton’s Second Law of Motion.”

LESSON PLAN PROCEDURE

Ask the students to discuss what a force is (a push or a pull). Ask for examples in everyday life. Ask for examples of force in football. Ask if the students have ever kicked a football (or some other type of ball). What types of forces are pushing on the ball?

What can you do to make the ball go higher or farther?

Tell the students: “Today we will discuss how force affects kicking a football.”

Introduce the concept of Newton’s 2^{nd} Law. The students can be given the Reading Guide or the teacher can lead the discussion.

__Paper Football Activity__

Obviously forces have a lot to do with football. But students probably should not play football in the classroom.

A fun way to play football anywhere and anytime is paper football (or finger football). It is a timeless classic, just like the real game of football. Also, it involves forces, just like the real game.

If you are not familiar with paper football, there are many tutorials on YouTube.com. A great one is:

Best How To Play Paper Football Tutorial Ever!

http://www.youtube.com/watch?v=aIlVe3yrMM0&feature=related

Now tell the students they are going to play paper football. Ask for a show of hands for all students who have played this before. Students will get paper and make paper footballs. They will then spend 10-15 minutes playing at their tables.

Tips: For help playing the game see the video referenced above. Students should wear safety glasses while playing this game, as field goal kicks could easily hit someone’s eye. The teacher may want to have several footballs premade in order to save time. The students could also be assigned to make footballs at home the night before.

__Online Force Simulation Game__

Next, the students will play a crude online version of paper football. The goal here is to think about the forces involved on the paper football.

Click on the link below. The site hosts a Newton’s 2^{nd} Law simulation, which can be useful for helping students learn about forces. After clicking on the link, click on the simulation image that appears on the screen.

http://phet.colorado.edu/en/simulation/forces-1d

The following link will take you to a video, which introduces a game (similar to paper football) that can be played using this site.

http://screencast.com/t/YmRjOTBk

Note: There are many other fun and useful simulations on the PhET website. Be sure to explore the other simulations available.

__Quantitative Virtual Lab__

Thus far, the discussion of Newton’s 2^{nd}Law has been qualitative (no numbers or measurements). The next activity will allow students to do an online lab and take virtual measurements of force and acceleration. This activity can be considered optional or an extension, if necessary.

This activity is designed to be a fairly simple exploration of Newton’s 2^{nd} Law. The students will note that as they increase the force, the acceleration will increase proportionally. If the students are able to find the slope of the graph they will note that it is 25 kg, which is the same as the mass of the dog. This is consistent with the relationship m = F/a.

There are many variations of this lab and the simulation is flexible enough to allow different types of exploration. In the chosen activity, the mass was kept constant and the force changed. Another option is to keep force constant and change the mass.

CLOSURE (REFLECT ANTICIPATORY SET)

Have the students reflect on how Newton’s 2^{nd} Law can be seen in the game of basketball or baseball. This can be verbal or written.

ASSESSMENT BASED ON OBJECTIVES

Newton’s 2^{nd} Law Quiz

POSSIBLE CONNECTIONS TO OTHER SUBJECTS

Physical Education/Fitness Class – students can practice kicking and punting.

Math – graphing and calculating.

English – written reflection on Newton’s 2^{nd} Law experience and how it applies to other sports.

ASSESSMENT BASED ON OBJECTIVES

Quantitative Lab can be treated as an extension activity or variations can be created using the online PhET Forces Simulation software.

ADDITIONAL NOTES

Activities can all be done as a unit or individual pieces can be taken and tailored as desired. Also, the PhET Simulations site contains other teacher lesson plans that can be downloaded.

NEWTON’S LAWS OF MOTION: READING GUIDE

__ __

Isaac Newton, the great scientist, provided us with three laws about forces.

1. The first, actually observed by Galileo, was that without a net force present, objects tend to persist (remain) in the current motion (at rest or constant velocity).

2. When a net force is present on an object, there will be an acceleration in the same direction as the force. This acceleration is related to how hard it is pushed (force) and its mass (F=ma).

3. A force is an interaction between two objects. Two objects must touch one another mutually with the same amount of force. This is often stated as ‘equal and opposite forces’, but in reality there is only one force acting on both objects.

__The 2 ^{nd} Law and Impulse__

The 2^{nd} Law is often expressed mathematically as F=ma. This is stated as ‘the force on an object can be calculated by its mass times its acceleration’. It can also be stated as ‘the acceleration of an object will be determined by the force exerted on it, divided by the mass of the object’ (a=F/m).

It is also true that the longer you push on a shopping cart with a steady force, the more you will cause it to accelerate (or gain velocity). This idea is known as impulse and can be expressed mathematically as Impulse = Force x Time. An impulse will lead to a change of the carts momentum (mass x velocity). Therefore, impulse is also described as the cart’s change in velocity.

__Units of Measure:__

Force is calculated by multiplying a mass value by an acceleration value. In physics mass is typically measured in kilograms (kg) and acceleration in meters per second per second (m/s^{2}). As a result, the units of force are kg ^{.} m/s^{2}. This unit is abbreviated as a newton.

__Acceleration:__

It should be noted that in physics when discussing acceleration, the term deceleration is not typically used. Rather, an object that is slowing down is said to have negative acceleration. This makes the discussion easier since objects speeding up or slowing down can both be said to have acceleration.

CONCEPTUAL QUESTIONS:

1. What is a net force?

2. Describe what happens to an object when a net force acts upon it?

3. A football sits at rest on the ground. Explain whether the forces on the football are balanced or unbalanced.

4. A girl rides a bike down the street at a constant speed. Explain whether the forces on the bike are balanced or unbalanced.

5. Discuss the velocity of a football that has been punted high into the air. Is there any acceleration on the ball as it rises and falls to the ground?

6. Is there a net force on a ball that has been punted into the air? If so, what is providing the net force?

7. Using the idea of Impulse, explain why a field goal kicker should ‘kick through the ball’, meaning extend their foot as high up as possible at the end of the kick.

8. Does this idea of ‘kicking through’ or ‘hitting through’ or ‘pushing through’ apply to other parts of football or in other sports? Explain.

9. Describe what happens to an object’s momentum if you push on it for twice as long.

10. Describe what happens to an object’s momentum if you push on it twice as hard.