Unit F: Chapter One

Unit F: Chapter One Forces and Motion

Science Question of the DayWhat causes the noise when you crack your joints?

_________________________________

_________________________________

_________________________________GravityGravity is a specific kind of _____________.A force is simply the ________ or a _________ on an object.Can you think of some examples of pushes and pulls on objects? __________________________________________________________________________________Take my soccer ball for exampleHow about my yo-yo

GravityKicking the soccer ball I am applying a force quickly to an object.Forces can also be added over ________________.What are some examples of forces applied over time?Think about my carOr an elevator

GravitySome forces are ___________________ acting on us.Gravity is an example of a ____________ that is always acting upon us no matter where we are!

Gravity: Take notes about the video here.__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

GravityEach piece of ____________________ in the universe no matter how large or how small _______________ on one another.This force is called ___________________.We see this most on Earth with how objects ________ ___ _______ ________________ like my bouncy ball. Our gravity keeps everything _____ the earth, even the oceans! If we didnt have __________ or we had a weaker __________________ force, our water and some of our atmosphere might ___________ _____ into space!GravityEven though gravity is what keeps us ______ the Earth, it is a pretty ___________ force. My bouncy ball and soccer ball _____________ have gravitational force. Do you think if I put them on the ground they will roll toward one another? ___________Lets find out

GravityWhat do you know about that? They didnt roll together!Why not?______________________________________________________________________________________Its not because of their size. ________ has nothing to do with gravitational force. It depends of the ____________ of the objects and the __________________ between them.Think about the planets. Jupiter is huge, but its gravitational pull is ______ stronger than say Uranus. Its all about the ________, baby!Mass and GravityThe more an object ______________ (weight is relative, but well use it here since we are all Earthlings, I think) the _____________ gravitational pull it has.Remember, we said that some objects can be very _____________, but ___________ a lot while some objects can be very __________ and weigh a ____________ amount.Take a marble and a beach ball for example. Which has more mass? ________________________________________________________________________________Distance and GravityThe _________________ you are to something the _________ gravitational pull you will feel.We notice this when we think about the sun and the Earth.The sun is about 330,000 times more ___________ than the Earth, but we feel the Earths gravitational pull _________because we are ______________ to it than the sun. Did you know that if you are standing on a mountain top you have ________ gravitational pull from the Earth than you do if you are standing at _____ _________?Can gravity be measured?Yes! Gravity can be measured in a unit called _______________.Any ideas as to why it is called a newton? __________________________________________________________When we step on the scale we are measuring the __________ of ____________ on ourselves. We can express our weight in _______________ just as we can in ________________ as newtons.Time for a laughWhen NASA first started sending up astronauts, they quickly discovered that _____________ _______ would not work in zero gravity. To combat the problem, NASA scientists spent a decade and $12 billion to develop a pen that writes in zero gravity, upside down, underwater, on almost any surface including glass and at temperatures ranging from below freezing to 300 C.

The Russians used a pencil.

Get it? The Russians Wow, that was funny!Time for a little practiceRead Gravity and complete questions 1-6 for homework.The teacher asked little Johnny, What is the definition of infinity?

Little Johnny replied, Tonights homework assignment.

Science Question of the DayWhy does pepper make you sneeze?

_____________________________________

_____________________________________

_____________________________________Speed and VelocityWhen you apply ____________ to an object, you are putting the object into _________________.We can observe the motion in many ways: Did the object move quickly? __________ Slowly? ______How far did the object go? __________________________Which direction did it move? _______________________

There are many ways in which we can observe motion.Two ways we are going to look at today are ___________ and _______________.Speed Lets think about a pitcher and a baseball.How fast is he or she really pitching and how can we determine this? ________________________________________________________________________________How far is the pitchers mound from home plate? ________________How long did it take for the baseball to go from the pitchers glove to home plate? ____________________The relationship between the ________ and the _______ is the ____________.

Speed To calculate the speed, you must ___________ the ____________ by the ____________. Lets try that in the classroom.How far am I from my volunteer? ________________How many seconds did it take for the ball to reach my volunteer? ______________________Lets do some math! ____________________________________________________________________________We just used a ratio in real life! Ms. White would be so proud!It is a comparison of the distance ___________ to time that __________________ during the motion.Speed We could even take this further and figure out how far my ball could travel in an hour.________________________________________________How many feet are in a mile? _____________________What equation could we make in order to determine how many miles per hour my ball traveled? ________________________________________________________________________________________________________

SpeedSpeed is difficult to calculate at a __________.For example, the wind could affect how quickly my ball is moving or the track in which it moves.If Im driving a car, I may speed up or slow down depending on traffic patterns.This is why we determine the __________ speed of objects.Heres an example: A trip from here to Disney World is 756 miles. This trip can be made in 12 hours and 49 minutes.What average speed must we go to get there in this amount of time? _____________________________________________ _____________________________________________________

Speed:Take notes about the video here.__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

Velocity Another way to observe motion is ____________.Velocity is the ________ of an object going _____ a particular ______________.Suppose two cars pass each other in opposite lanes of an east/west highway. Both cars are traveling at 75 mph, so both have the same speed. But the cars are going in different direction, so they have ___________ _______________.One car has a velocity of 75 mph heading east and the other is 75 mph heading west.

VelocityVelocity is simply _________ with a _______________.Think about a race car on a circular track.The speed may stay ____________, but the velocity changes when the car changes ___________________.

MomentumCould you tell the difference between a bowling ball that was painted like a soccer ball and a real soccer ball rolling down a bowling lane? ________________When they hit the pins you could! The bowling ball would knock the pins over, but the soccer ball would only move a couple of pins.This is because the bowling ball is ______________ and would have more ______________________.

Momentum________________ is the measure of how hard it is to ________ _________ or _________ an object that is in motion. Think about football players. Is it easier to stop the quarterback or the lineman? ____________________Duh, the quarterback because he is smaller and lighter. You can determine the ________________ of an object by _________________ the _________ ____________ the velocity.

MomentumLets figure out the momentum of the bowling ball.The ball weighs 8 lbs.It is traveling at 3 mph.What is its momentum? How about the soccer ball?It weighs 1 lb. It is also traveling at 3 mph.What is its momentum?Obviously, the bowling pin is the linebacker in this example.

Conservation of MomentumWhen the bowling ball struck the pins it created a collision.There is a law of science that states that an objects momentum ______________ a collision stays the _________ as momentum _____________ the collision if no other forces act on the object.We can see this by the bowling pins absorbing the force of the bowling pin and scattering in the lane.This is called the ________ of the ________________ of momentum.Time for a little practiceRead Speed and Velocity and answer questions 1-6 for homework tonight.

Science Question of the DayWhat is static electricity and how does it work?

The Laws of MotionThere are several laws that were discovered by scientists thousands of years ago that describe how objects move.

We all know about Newton and gravity, but some you may not have heard of are Galileo, Aristotle, and Ptolemy.

Over the next few days, we will discover Three Laws of Motion.

First Law of MotionAn object at _______ tends to ________ at rest, while an object in _____________ tends to stay in _________ in a straight line until an ___________ force acts on it.What does this mean?

Objects do not change their velocity unless some force _________ on them.Example: A hockey puck sitting on the ice does not move until something makes it move.The puck will continue to travel in the same direction across the ice until a stick changes it or friction slows it down.

FrictionFriction is a force that ___________ motion whenever _________ surfaces rub against each other. Friction is only present when other forces such as ____________ or _________ ___________ are present and act to _______ an object against something else.Friction is what causes objects that are rolling to ________ once the energy that keeps them moving is ________ than the energy that was required to make them move.Lets roll this ball and see what happens.InertiaObjects tend to ____________ a change in motion. For example, when you are in your car and you go around a curve, your body tends to want to go in the opposite direction. This is because of ______________.This is the property that makes it hard to __________ a car when it is parked, or _________ to stop it once it is moving. Sometimes the first law is called the ______ of ________, but inertia is not a law; it is a ______________. Balanced & Unbalanced ForcesBefore we can learn about the Second Law of Motion, we must first learn about ____________ and _________________ Forces.Which one of these pictures if balanced? Unbalanced?

Balanced ForcesWe have been learning about forces such as gravity, inertia, friction, etc. Most of the time, object have _________ than one force acting on them at a time. A ball rolling across the floor is experiencing all three of the above stated forces.________________ forces are forces that are acting _______________ on an object, but are acting in ________________ directions. Balanced ForcesWhen the forces are balanced, either the object does _______ move, or it moves at a constant ___________. This is called the ________ _____________.Think about a skier. What forces of motion are acting on him? _______________________________________

Balanced ForcesThe skier continues down the slopes because the forces of gravity, inertia, and friction are all _____________.Once he reaches the bottom of the slopes, the force of ___________ will overtake the forces of gravity and inertia, and the skier will eventually stop.This is when ____________________ Forces take over.

Unbalanced ForcesUnbalanced forces cause a _________ in velocity making the object speed up, slow down, or change direction. In a game of tug of war, two teams are ___________ on the rope. If they are both ___________ with equal force, than the forces are _________________ and the net force is ______________; the rope does not move.However, if a team pull harder, then the rope starts to move in their direction. This is an unbalanced ___________.

Unbalanced ForcesThink about the following scenarios. How are unbalanced forces acting on the objects?Speeding up a carSlowing down a carChanging the direction of a car

Heres a hint: friction!Forces:Take notes about the video here.__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

Time for a little practiceRead Balanced and Unbalanced Forces and answer questions 1-5 for homework due tomorrow.

Science Question of the DayHow and why do cats purr?

Second Law of MotionThis law explains how an _________________ force changes the motion of objects. The __________ of an object is equal to its mass _______ accelerationWhen unbalanced forces act on objects it ___________ the ___________ of the object (its speed, direction, or both).The rate of this change is called ______________________.This law states:The ___________ the force, the greater is the _____________, or change in __________________.The greater the ___________, the __________________ is the acceleration or change in velocity.Second Law of MotionSo basically, the ________________applied, the __________ it will go. The ______________applied, the _________________ it will go.And, the _____________you have in an object, the _____________________is needed for acceleration,Take a miniature car for example vs. a real one.I can push the miniature with one finger with very little effort, and it shoots forward.If I tried to do that with my car I would probably break my finger.

Second Law of MotionThe _________________ in which force is applied is the direction in which the object ________________.For example, if an object is already moving and we push it from behind it will simply speed up.Lets have a little race.

Second Law of MotionIf the _________ is applied from the _______________ direction the object is moving, then it will __________ down the object. For example, if we were to play bumper office chairs (and we wont for safety sake), and I were to push my chair into someone elses chair then it would slow down or stop their motion. We see this in front-end collision crash tests.

Third Law of MotionFor every __________ force, there is an ________ and __________ reaction force.This basically means that forces always come in pairs. For example, as I am pushing down on this floor with my feet, the floor is pushing back.The forces are always ___________ and ____________.If the floor did not push back, I would fall right through.

The Laws of Motion:Take notes about the video here.__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

__________________________________________________________

Time for a little practiceYou and a partner will be rotating through several mini-experiments and recording your results over the next few days. All the activities are designed to help you understand the different laws of motion. At the end of each rotation you will fill out your research guide. This is your final product that will be due next week.Please make sure your put effort into your research guides as they are worth 100 points!