12.3.12 newton’s 1st Law

12.3.12newton’s 1st Law • Objective: The student will investigate and describe applications of Newton’s law of inertia, law of force and acceleration, and law of action-reaction such as vehicle. • Starter: **Write the problem in your STARTER section** Count the atoms in the following formulas: 4 Al2(SO3)3 2 (NH4)3PO4 5 ZnSO4

P: Vocab Break Down • Objective: The student will investigate and describe applications of Newton’s law of inertia, law of force and acceleration, and law of action-reaction such as vehicle.

Investigation: to observe or study by close examination and systematic inquiry • Describe: to represent or give an account of in words describe a picture; to represent by a figure, model, or picture.

Newton: A unit of measurement for force, named after Sir Isaac Newton. • Inertia: The tendency of an object to resist any change in its motion.

Law: A body of observations. Scientific laws explain things, but they do not describe them. One way to tell a law and a theory apart is to ask if the description gives you a means to explain 'why'. • Force: A push or pull.

Acceleration: When the velocity of an object changes • Action: Is an assertion about the nature of motion from which the trajectory of an object subject to forces can be determined. • Reaction:

Newton’s 1st Law • “An object at rest, tends to stay at rest, and an object in motion, tends to stay in motion with the same speed and in the same direction, unless acted upon by an outside force.” • Objects resist change in motion. • The more mass an object has, the greater its inertia. • Bill Nye Inertia

A- Inertia Cup activity • Write these questions and answer: • What happened to the water as it was being passed around? • Explain how this activity relates to Newton’s 1st Law? • Explain what inertia had to do with this activity. • Think of another example of inertia. Explain your example.

C- • What is the effect of force when (what happens to the force): • Brakes are applied to a moving car • A football lying on the ground is kicked • A basketball player catches a pass

E- Reflection • Write about today’s lesson. Use the key words such as force, speed, unbalanced force, energy. Be sure to write about the activity and how it demonstrated Newton’s Laws! Now describe what example you will be using for you Newton’s Law Project, and how it relates to todays lesson.

12.5.12newton’s 2nd Law • Objective: The student will investigate and describe applications of Newton’s law of force and acceleration, by looking at different examples. • Starter: • Draw and label the Bohr model of Beryllium. Write how many protons, neutrons, electrons, and valence electrons

TEK Break down • Objective: The student will investigate and describe applications of Newton’s law of force and acceleration, by looking at different examples.

P- Newton’s 2ndLaw of Force and Acceleration Write these questions in your journal: 1.Which vehicle will accelerate more quickly? Why? 2. Which vehicle will be more difficult to move? Why? (Use your vocabulary words) It takes more force to move an object with a larger mass and they accelerate at a slower pace. However, once moving they are more difficult to stop. It takes less force to move an object with a smaller mass and they accelerate at a faster pace. They will come to a stop faster than a more massive object

For example… F=ma F=ma If the force remains constant, smaller masses will have greater acceleration compared to larger masses. If the force remains constant, larger masses will have less acceleration compared to smaller masses.

For example… small mass = greater acceleration large mass = less acceleration

Newton’s Law of Force and Acceleration If the mass of an object remains constant, then accelerationincreases as the force increases. ALWAYS identify the force, mass, and acceleration variables to see which ones are constant.

Recap Video • Newton's 1st Law and Football • Newton's 2nd Law and Football

A- Agree/ Disagree/Justify Scenario: 50 N of force is applied to three different masses of balls. Ball A- 70 g ball Ball B- 50 g ball Ball C- 30 g ball 1. Use the formula F = ma to calculate the acceleration of each ball. Explain the process. Note: Since a Newton is equal to kg/m/s/s, we must first convert our mass to kg. (grams ÷ 1000 or move the decimal three places to the left) You may use a calculator to do this. 2. Agree or disagree with the following statement, and support your answer with evidence using Newton’s laws. Ball C will travel the farthest distance, while Ball A will travel the least distance.

C- Sketch a real life example of the 2nd law with a description. • E- Using 5 vocabulary words recap on what we learned today

12.5.12newton’s 3rd Law • Objective: The student will investigate and describe applications of Newton’s law of action-reaction. • Starter: **Write down the steps you took to get your answer** • What is the speed of a jet plane that travels 528 meters in 4 seconds? • How much force is required to accelerate a 50 kg mass at 4 m/s2?

P- Newton’s Law of Action-Reaction "For every action, there is an equal and opposite reaction." Reaction Action

Newton’s Law of Action-Reaction All forces act in pairs. The action force acts on one object, while the reaction force acts on a second object. This is not a cause-effect relationship. The forces occur simultaneously. Newton’s 3rd Law in Football

A. Write the question down Each Question and answer in your journal

Write the question down Each Question and answer in your journal

3. A tennis racquet hits a tennis ball. Why doesn't the racquet swing backwards when the ball hits it? (Shouldn't it swing back because of action-reaction forces?) 4. How is shooting a shotgun related to Newton's Third Law? The racquet does not swing backwards because the force of your arm keeps it from going back. The action force is the ball hitting the racquet (which your arm “absorbs”), the reaction force is the racquet pushing back on the ball causing it to go back across the net. When shooting a gun the action force is the gunpowder in the shell pushing on the little BB’s in the shotgun shell. The reaction force is the BB’s pushing backwards. This backwards force gets transferred to the gun and eventually to your shoulder (holding the gun). This is known as the “kick” of the shotgun.

C- • Name 3 examples of Newton’s action-reaction law and how it can be applied to real life. Examples must be different examples from the one’s we have discussed today.

E- • Label what law applies to the following: • An apple falls from a tree and hits you on top of the head. • You are in a car and the person driving suddenly slams on the brakes. Your body leans forward but your seat belt keeps you in the seat. • Consider the flying motion of birds. A bird flies by use of its wings. The wings of a bird push air downwards. In turn, the air reacts by pushing the bird upwards

12.3.12 newton’s 1st Law