Bell Work 4/22/14 – 5 min Turn in your lab! New Bell Work Titled “Laws of Motion!!!!!!!!!” 1.Who was Issac Newton? 2.List at least 3 forces! 3.W5SAYWoS.

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Bell Work 4/22/14 – 5 minTurn in your lab!

New Bell Work Titled “Laws of Motion!!!!!!!!!”

1. Who was Issac Newton?

2. List at least 3 forces!

3. W5SAYWoS

Schedule • Friday– Finished friction labs. Turn in now!– Quizzes madeup– Received quiz grades & updated grades– Easter Bunny! – due Wednesday

• Tuesday – Notes on

• Tuesday – Grades

Today you are going to…read about and take notes on Newton and Newton’s 1st Law of Motion.

So you can…know who Newton is, what he did, and how his first law is applied.

You’ll know you’ve got it when you can • Accurately complete the notes sheet & questions

Issac Newton• VIDEO!

Issac Newton• Born Christmas 1642

• Failure as a farmer

• Was waiter in college to pay for first 3 years

• 1664 Elected a scholar…free school! • 1665 Plague closed his school 1665

Issac Newton• Worked on math & physics at home for 2

years

• figured out law of gravity, optics, and calculus

• 1667 worked on alchemy

• Invented reflecting telescope

• King Charles II excused Newton from taking holy orders

Issac Newton• 1686 published Principia• Changed man’s views on universe• Appointed Master of Mint in London• Knighted by Queen Anne• Argued with people about who should be credited for

invention of calculus & gravitation• VIDEO!

Newton’s 1st Law of Motion

• An object An object at rest stays at rest at rest stays at rest and an object and an object in in motion stays in motion motion stays in motion with the same with the same speed and direction speed and direction unless acted on by an unless acted on by an unbalanced forceunbalanced force. . – Objects "tend to keep on doing what they're Objects "tend to keep on doing what they're

doing.“doing.“

• Sometimes called the Sometimes called the law of inertialaw of inertia

Bell Work 4/16/12 – 3 min1. Write Newton’s 1st law of motion.

2. Draw a picture representing the forces on the coffee mug sitting on the desk.

• An object An object at rest stays at rest at rest stays at rest and an object in and an object in motion stays in motion motion stays in motion with the same speed and with the same speed and direction direction unless acted on by an unbalanced forceunless acted on by an unbalanced force. .

• If an object is at rest, it will stay there If an object is at rest, it will stay there forever… forever…

• unless an unless an unbalancedunbalanced force pushes or pulls force pushes or pulls it. it.

• What’s an unbalanced force?

• It’s the same as a net force!

Newton’s 1st Law of Motion

• If you start an object moving, it will keep moving with a constant velocity forever unless something pushes or pulls on it.

• A force is not required to keep things moving…it’s required to make them stop (or turn)!

• Why don’t we notice this? – Friction (& air resistance) slow down & stop

moving objects

Newton’s 1st Law of Motion

An object in motion stays in motion with same speed & direction unless

acted on by a net force• If an object is at rest, the net (total) force

on it is _______!

• Is it accelerating?

• Inertia – object’s resistance to a change in motion. (It’s NOT a force!)– Mass is a measurement of inertia

• Measured in kg• Glass of water example!

Inertia

Inertia

Inertia

Inertia

Free Body Diagrams!!!!

Inertia

Inertia

Inertia

• If an object has a constant velocity, the net (total) force on it is ________!

• Is it accelerating?

An object at in motion stays in motion with same speed & direction

unless acted on by a net force

Bell Work 4/18/13 – 5 min1. Write all aspects of Newton’s 1st law.

2. The head of the hammer is loose. How could slamming it on a surface as shown work to tighten it? Why would it be better than doing it the other way? (diagram b)

A. B.

Newton’s 1st Law of Motion

• An object An object at rest stays at rest at rest stays at rest and an object and an object in in motion stays in motion motion stays in motion with the same with the same speed and direction speed and direction unless acted on by an unless acted on by an unbalanced forceunbalanced force. .

• Sometimes called the Sometimes called the law of __________law of __________

Examples of Newton’s 1st law

• A car has the cruse control on. What are the forces acting on the car? What is the net force acting on the car?

• The car wrecks into a tree. How is Newton’s 1st law related to what happens to the objects inside the car?

• Marble in a pan!!

Bell Work 4/19/13 – 5 min1. To get the ketchup out of a ketchup bottle,

Robert turns upside down and thrusts downward at high speeds and then abruptly halted.

2. Where would you like to sit?

Schedule • Thursday– Finish Newton’s Laws of Motion Demo Sheet– Finish Newton’s 1st Law

• Friday– Newton’s 2nd Law – F = ma

• Monday– Begin 11.2– Review for quiz

• Tuesday– Newton’s 3rd Law or 11.2 – Quiz on Newton’s 1st & 2nd Laws

• Blood rushes from your head to your feet while quickly stopping when riding on a descending elevator.

• The head of a hammer can be tightened onto the wooden handle by banging the bottom of the handle against a hard surface.

• A brick is painlessly broken over the hand of a physics teacher by slamming it with a hammer. (CAUTION: do not attempt this at home!)

• To dislodge ketchup from the bottom of a ketchup bottle, it is often turned upside down and thrusted downward at high speeds and then abruptly halted.

• Headrests are placed in cars prevent whiplash injuries during rear-end collisions.

• While riding a skateboard (or wagon or bicycle), you fly forward off the board when hitting a curb or rock or other object that abruptly halts the motion of the skateboard.

• Cement block broken on chest of someone laying on bed of nails

• Hammer nail into board on a few books on someones head

Preguntas

• T or F: If Fnet = 0 than V = 0

• What causes a moving object to change direction?

Preguntas

If the forces acting upon an object are balanced, then the object

a. must not be moving.

b. must be moving with a constant velocity.

c. must not be accelerating.

d. none of these

Newton’s 2nd Law of Motion• When a net force acts on an object, the

acceleration that results is:1. _________proportional to the force

2. _________ proportional to the mass.

3. in the same direction as the net force.

a = Fnet .

m

Fnet = ma• Remember to use the NET FORCE (total force) in

this equation.

Newton’s 2nd Law of Motion• Our abbreviated version of Newton’s 2nd Law:

• Fnet = ma; the force and acceleration are in the same direction

Newton’s 2nd Law of Motion• The acceleration resulting from a net force

is directly proportional to the force.

a = Fnet .

m

If the force doubles, what would happen to the acceleration?

Newton’s 2nd Law of Motion• The acceleration resulting from a net force

is inversely proportional to the mass.

a = Fnet .

m

If the mass doubles, what would happen to the acceleration?

Newton’s 2nd Law of Motion• When a net force acts on an object, the

acceleration that results is in the same direction as the net force.

Kind of tricky thing…the object won’t necessarily go that direction, but it will accelerate that direction. (That might just mean turning in that direction or slowing down.)

• English unit of force is the pound. • SI unit of force is the Newton. • The Newton is the amount of force required to

give 1 kg of mass an acceleration of 1 m/s2.

Fnet = ma

• How much horizontal net force is required to accelerate a 1000 kg car at 1 m/s2?

2 m/s2? 3 m/s2?

Online Problems

• http://www.batesville.k12.in.us/physics/Phynet/Mechanics/Newton2/Second_Law_Quiz.html#concept%20quiz

STOP

1st Law Video

Newton’s 2nd Law Video

Bell Work 3/31/11 – 4 min

1. Force is __ related to acceleration

2. If the force doubles, the acceleration __.

3. Mass is __ related to acceleration

4. If the mass doubles, the acceleration __.

5. One Newton will make 1 kg accelerate at a rate of __.

6. How many Newtons will it take to make a 100 kg object accelerate at 500 m/s2?

Improvements• I think that normal force and friction need to be covered in

this section. Also maybe something about looking at force diagrams and telling what an object will do…what direction it will accelerate. Add velocity in there too…this could help us lead to circular motion! Like if its moving right and it accelerates down, what will it’s path look like. Stress that net force and acceleration are same direction.

• Maybe friction was talked about earlier…if so, we should have included normal force then.

• Include the idea of relative velocity…everything is moving!• Include floating meter stick for adding forces together

(multiple students try to touch it)• For freefall…drop bottle with holes in it and it’ll stop spilling

water,

Improvements• Freefall! – have students determine reaction time with

note card

Bell Work 4/16/12 – 5 minutes1. If you were on the surface of Pluto, how would

your mass and your weight compare to when you’re on Earth. Why?

2. W5SAYWoS

Schedule • Monday– Finish reviewing ze study guide– Review what’s on test– Students ask questions!

• Tuesday– Jeopardy!

• Wednesday– Test!

• Thursday– Work & Energy Reading Guide

• Friday– Work & Energy Notes

What’s on test?

• Gravity & Projectile Motion Study Guide– All except # 2, 9, 14-16, 18

• Circular Motion – All except 8

• Chapter 11 Study Guide– All

• Newton’s 3rd Law Review– All (5 questions)

Skip slide!

• Cool video with inertia and stuff

• What about how fast you pull and inertia?

• http://www.youtube.com/watch?v=32q1g7lHAFQ

Bell Work 3/27/12 – 4 min1. What is one strange experiment conducted by

Newton?

2. What book did Newton write?

3. Convert 80.0 lbs to Newtons using the factor label method. Show your work.

4. What force is required to give a 5.0 kg object an acceleration of 3.0 m/s2? Show your work.

Bell Work 3/26/12 – 4 min1. Convert 150.0 lbs to Newtons using the factor

label method. Show your work.

2. A force of 80.0 N acts on a 5.0 kg object. What’s it’s acceleration?

Bell Work 3/26/12 – 4 min1. A force of 80.0 lbs acts on an object with a

mass of 5.0 kg. What’s it’s acceleration?

Bell Work 4/13/12 – 4 min1. Take your homework out & place it upside

down on your desk.

2. Bill has a mass of 65 kg. Find his weight in Newton’s.

3. Convert bill’s weight to pounds using the factor label method.

To Study For Test

• gravity & projectile motion study guide

• 10 Questions on Circular Motion wkst– Back of gravity & projectile motion study guide

• 5 Questions on Newton’s 3rd Law Review!

• Chapter 11 Study Guide

Bell Work 4/4 – 5 min1. F = ? M = 20.0 kg a = 8.5 m/s2

2. If a force of 20 Newtons is exerted on a 5 kg ball, what will it’s acceleration be? (F=ma)

• Study 11.1 Laws of Motion Reading Guide, Demo Sheet, & your notes

• State all aspects of Newton’s 1st Law

• Explain an example of Newton’s 1st Law

• Define inertia

• Define mass

Preguntas

• T or F: If Fnet = 0 than V = 0

• What causes a moving object to change direction?

Preguntas

If the forces acting upon an object are balanced, then the object

a. must not be moving.

b. must be moving with a constant velocity.

c. must not be accelerating.

d. none of these

TT

TT

Kylie Marie Gansor & Sam Arnold

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