PHYSICS

January 7, 2019  Monday
Welcome to Physics.
Please get the Syllabus and safety contract signed by your guardian by January 11th
Begin "Measuring Your surroundings Lab"

January 8, 2019 Tuesday
Finish "Measuring Your Surroundings Lab"
Metrics Conversion Worksheet

January 9, Wednesday
Dimensional analysis

January 10 Thursday
Finish Dimensional analysis
Exponent rules  powerpoint/problems

January 11, Friday
Understanding check on Dimensional analysis and Metrics
Graphing

January 14 Monday Finish Graphing and do Precision lab
January 15 Tuesday- Scientific notation pwpt .  Begin Scientific method- building bridges competition
January 16 Wednesday -  Finish building bridges competition
January 17- Thursday Physics basics quiz
January 18 - Friday Speed and vectors

Jan 22 Monday  - Continue vectors
Jan 20-   Tuesday- Speed versus velocity notes and problems
Jan 21 Wednesday- speed versus velocity problems
Jan 22  Thursday cover graphing
Jan 23 Friday - Marble velocity lab
Jan 26 Monday - test review
Jan 27- Speed and velocity test
January25   Friday   Marble lab
January 28 Monday- Review and graphing mastery quiz .Also  formulas mastery quiz
Jan 29 Tuesday speed and velocity test
 Monday feb 4, 2019 Understanding check on acceleration with remediation.Acceleration concepts introduction
Tuesday feb 5 2019 Acceleration problems levels 1 and 2
 Wednesday, feb 6, 2019 absent students watch a physics video
Thursday, feb 7, 2019. Finish notes on acceleration. Students continue to do problems
Friday feb 8- Acceleration problems followed by free fall lab
Monday Feb 11- Review for test on Acceleration and free fall
Tuesday Feb 12- Test on Acceleration and free fall. Projectiles vocab

AHS Physics – Ch. 3 Test Review sheet key
 1.     Objects fall at constant _____ ( no air resistance present) Ans. Acceleration
2.     Compare the speed of a ball is thrown upwards and caught when it comes back down at the same height. Ans. same
3.         An object is in free fall. When can be said about the distance it falls each second?  Ans. Increases
4.     If air resistance is present and a feather and a bowling ball are dropped which would arrive first?  Ans. Both would arrive at the same time.
5.         A ball is thrown up. What is the instantaneous speed of the ball at the top of it’s path? Ans. Zero
6.         A ball accelerates due to the earth’s gravitational pull. What is the value of g? Ans. -9.8m/s2
7.         What conditions were met if a car travelling down the road did not accelerate? Ans. speed increases, decreases, or direction changes
8.         What does a car’s speedometer tell you?   Ans. Instantaneous speed
9 What is the definition of  acceleration (hint: describe the formula). Ans. Rate at which speed changes over a period of time
10. Is a car driving at 60 miles per hour around a curve accelerating? Ans. Yes changing direction
11. A bicycle is going in a straight line at 2 miles per hour for the first second, 2 miles per hour for the second second, and 2 miles per hour for the third second. Is it accelerating? Ans. Yes
12.       What is the speed of a falling object after 9 seconds? Ans. 90m/s
13.       Define free fall. Ans. only force that acts on the object is gravity
14.  You are travelling at 20m/s north and than turn around and go at 20 m/s south. What is the change in velocity? Ans. change in velocity is final velocity –intial velocity= -20-20= -40m/s
15.       Draw a particle model of an object negatively accelerating. Ans. .      .        .    . . ..
16.       What does acceleration due to gravity depend on? Ans. force exerted by the planet
17. You throw a ball up what happens to it’s velocity? What happens to the velocity as the ball comes down?  Ans. Increases when it comes down.
18. What happens to the acceleration when a ball is throw up? Ans. stays the same
19. What happens to the acceleraton when a ball is coming downward? Ans. stays the same

20.  What is your average speed if you run 280 meters in 4 seconds?
Average speed= d/t
Speed= 70m/s
21. How much distance will Pedro travel if he maintains a speed of 60.0 km/hr for 2.0 hours?
Ans. d=st        d= 120m
22. What is the acceleration of a ball that starts at rest and rolls down a ramp, gaining a speed of  35 m/s          in a 4.0 second time frame?
Ans. 35/4= 8.75m/s
23. An apple drops from a tree and hits the ground in 8 seconds. What is its speed just before it hits the          ground?
Ans. 80m/s
24. Using the information from question #24, what is the distance from the branch (which the apple fell) to the ground?  d= 313.6m
25. Compare and contrast velocity and acceleration.

Ans. Velocity is displacement over a period of time while acceleration is the change in velocity over time


Wednesday feb 13- Newton's first law
Thursday feb 14 Newton's first law problems

Friday- Feb 15 Quiz on Newton's first law

FORCES continued
Feb 25  Monday  Inquiry lab on forces
Feb 26  Tuesday Newton's second law
Feb 27 Wednesday Newton's third law
feb 28 Thursday Review
STUDY GUIDE ANSWERS:
PHYSICS HONORS
Ch 4: Forces Test Study guide answers
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Vocabulary to Know in Context:
  1. Dimension
  2. Vector
  3. Scalar
  4. Resultant
  5. Velocity
  6. Speed
  7. Mass
  8. Weight
  9. Acceleration
  10. Displacement
  11. Force
  12. Static Friction
  13. Kinetic Friction
  14. Inertia
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Concepts and Questions to Know:
  1. What is the difference between constant and instantaneous speed?  Which one do you see on your car’s speedometer? 
Ans. Constant speed is when there is no change in speed over a period of time while instantaneous speed is speed at a particular instant as measured by a speedometer.
  1. What does the slope of a distance vs. time graph tell you (hint:  slope = rise/run)?
Ans. speed
  1. What does the slope of a velocity vs. time graph tell you?
Ans. Acceleration
  1. Can you have constant velocity and constant acceleration at the same time?  Why or why not?
Ans. No because if the velocity is constant that means that there is no acceleration taking place.
  1. If a car travels at a constant speed in the same direction, what is the car’s acceleration?
Ans. Acceleration is zero
  1. What is the acceleration due to gravity?  Why is it always negative?
Ans. -9.8m/s2
  1. What does the term “free fall” mean?  How fast is an object accelerating if it’s in free fall?
Ans. Acc due to gravity is -9.8m/s2
  1. Do all objects fall at the same speed regardless of mass?  Under what conditions would there be a difference in free fall? Ans. all objects gall at the same speed regardless of mass. Difference comes  with amount of distance fallen
  2. What is a force?  What units is it measured in? force is a push or a pull. Unit for force is Newtons
  3. What is inertia?  Is inertia a force? Ans. Inertia is directly proportional to mass. It is not a force.
  4. When the mass is increased, what happens to the inertia? Ans. It increases
  5. Can an object be moving and still have inertia?  Under what conditions? Ans. As long as an object has mass it has inertia.
  6. Why does your body want to keep going forward after an accident when the car has already stopped? Ans. It has inertia
  7. What do forces produce? Ans. Forces produce acceleration.
  8. If an object is moving with a constant velocity, what is the net force acting on it? Ans. zero
  9. Give an example of something with no net force acting on it but still moving. Ans. A ball in space
  10. When you increase the mass of an object but apply the same amount of force, what happens to the acceleration?Ans. Decreases
  11. What is friction?  Give three examples of friction? Ans. Friction is a force acting in the opposite direction of motion
  12. What is a free body diagram and what is it used for? Ans. see next problem
  13. What forces are shown on a free body diagram? Ans.  A free-body diagram  is a representation of a certain object showing all of the external forces that acts on it
  14. What type of force is air resistance? Ans. It is a type of friction.
  15. The force related to gravity is called what? Ans. Weight
  16. What is the name of the force that results from a surface pushing back up on an object?
Ans. Normal force
  1. What is net force? Ans. sum of all forces
  2. What is an object’s net force when it is in equilibrium? Ans. Zero
  3. List Newton’s three laws of motion in YOUR OWN WORDS and give examples of each.
Ans. notes- first law is law of inertia. An object keeps moving at constant velocity or is stationary unless acted upon by an unbalanced force. Second law is F=ma. If the mass of an object is increased 2 times then 2 times the force is needed to move it (please refer to notes) and third law is for every action there is an equal and opposite reaction
  1. What is the normal force of an object in free fall? Ans- none
  2. What is the difference between static and kinetic friction? (omit)
  3. What is the coefficient of friction?  What are its units?  Is the coefficient of static or kinetic friction always bigger between two objects?  Why?  As the coefficient of friction for between two objects gets bigger, what happens to the friction force? (omit)
  4. According to Newton’s third law of motion, for every action there is an equal and opposite reaction.  So how does anything ever accelerate? Ans. There is an unbalanced force on that particular object.
  5. Name 3 action-reaction pairs. Ans. You push on the wall and the wall pushes back on you
  6. If a truck and a car collide together, which has the bigger force?  Which has the bigger acceleration? Ans. both have the same force acting on them only the acceleration is different. The car will accelerate more because it has less mass.
  7. What is the difference between mass and weight?  Which one changes with your location?  Which one remains the same no matter what? Ans. Mass is the amount of matter in an object and stays the same while weight is a function of gravity and can change with location
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Practice Problems:

  1. Draw a free body diagram of:
    1. a hockey puck that is moving with a constant velocity across a frozen pond.  (ANS:  W down, N up, movement lines behind the puck)
    2. a stubborn dog, being led on a leash uphill, refusing to move…even though its owner is pulling on the leash (ANS:  W down, N up at an angle perpendicular to the ground, T along the leash, friction or Fpush or both the opposite direction of the T force)
    3. A person skydiving who has reached her terminal velocity (ANS:  W down, f up, movement lines above the body)
  2. A car is accelerating at a rate of 4.5 m/s2.  If the car has a mass of 1500 kg, what is the net force acting on the car?  (ANS:  6750 N)
  3. A ball with a mass of 20 g has a net force of 0.34 N acting on it.  What is the ball’s acceleration?  (ANS:  17 m/s2) 
  4. A force of 75 N headed west intersects with a force of 145 N headed south.  What is magnitude and direction of the net force?  (ANS:  163 N @ 63° S of W   or  163 N @ 27° W of S)
  5. A car is broken down on the side of the road.  If two people get out and push the car, on with a force of 155 N and the other with a force of 201 N, what would the friction force be for them to get the car moving at a constant velocity?  (ANS:  356 N in the opposite direction of the people pushing it)
  6.    A football is thrown across a 97 m football field.  If the 1.5 kg football takes 2.3 seconds from rest to cross the football field, what was the net force acting on the football?  (ANS:  13.8 N)
  7. A cart is rolling down a hill at constant velocity of 20.3 m/s.  If the 35 kg cart travels for 45.6 seconds, what is the net force acting on the cart?  (ANS:  0 N)
  8. What is the weight on Earth of a 85 kg person?  What is the weight of that same person on the moon where the gravity is 1/6 that of Earth’s?  What is the person’s mass on the moon?(ANS:  850 N; 142 N; 85 kg)
  9. If an object weighs 770 N on Earth and has a weight of 2304 N on another planet, what is the acceleration due to gravity on this new planet?  (ANS:  29.9 m/s2) 
  10. A boy, with a mass of 35 kg, is riding a bike, with a mass of 15 kg, is moving at a constant velocity along the pavement.  If the coefficient of kinetic friction between the tires and the ground is .58, what is the friction force acting on the boy and the bike?  (ANS:  232 N)
  11. A 15 kg chair is at rest on the floor.  It takes 130 N of force to get it moving and to keep it at a constant velocity a force of 115 N has to be continually applied to it.  What are the static and kinetic coefficients of friction?  (ANS:  0.87 and 0.77)

March 1 Friday  Test


Webquest

­­Momentum Webquest
http://www.batesville.k12.in.us/Physics/PhyNet/Mechanics/Momentum/momentum.htm
Use the information on the website to answer the questions below.

Review: What is velocity? ____________________________________________________________________

What is momentum?_________________________________________________________________________

Does an object at rest have momentum?__________________________________________________________

What is the formula for momentum?____________________________________________________________

Why does a slow-moving bus have a large momentum?  ____________________________________________

Why does a small bullet have a large momentum? _________________________________________________

HIT THE FORWARD ARROW AT THE BOTTOM OF THE PAGE
IIMPULSE MOMENTUM
What the heck is impulse momentum?  According to this site:
Impulse = ____________________________________

HIT THE FORWARD ARROW AT THE BOTTOM OF THE PAGE
GETTING THE LARGEST POSSIBLE VELOCITY
What is another way of saying, “largest possible velocity?” __________________________________________

Why does a tennis ball have almost zero momentum before a serve? ___________________________________

What is the equation for impulse? ______________________________________________________________

Name 3 ways you can get the largest impulse on a tennis ball?
_______________________________________________
_______________________________________________
_______________________________________________

How does “follow through” help in tennis, baseball and other sports? __________________________________
__________________________________________________________________________________________

HIT THE FORWARD ARROW AT THE BOTTOM OF THE PAGE
GETTING THE SMALLEST POSSIBLE FORCE

What is another way of saying “getting the smallest possible force”?___________________________________

Review: What is the formula for impulse? _______________________________________________________

In the example of jumping off a chair, what is the impulse that will stop your fall? _______________________

Which of Newton’s Laws is this? _________________________

Can you decrease your velocity before hitting the floor? _____________________

In order to decrease the force of the impulse on the floor, what must you increase?  _______________________
Go to the following link to complete the rest of the web quest: http://www.physicsclassroom.com/Physics-Interactives/Momentum-and-Collisions

Click on the fish catch interactive. Click Launch Interactive. Begin activity.  Record the data from the interactive below for 4 different collisions.

Before Crash
After Crash

Mass (g)
Velocity
Momentum
Velocity
Momentum
Big fish





Little fish





Total








Before Crash
After Crash

Mass (g)
Velocity
Momentum
Velocity
Momentum
Big fish





Little fish





Total








Before Crash
After Crash

Mass (g)
Velocity
Momentum
Velocity
Momentum
Big fish





Little fish





Total








Before Crash
After Crash

Mass (g)
Velocity
Momentum
Velocity
Momentum
Big fish





Little fish





Total






  1. What is the equation for momentum?



  1. What pattern do you observe with the total momentum before and after the launch?
 


  1. How does the size of the small fish influence the velocity of the big fish?



  2. How does the total mass (small + big fish) influence the momentum of the fish together?


  1. Why?  Think about the equation for momentum. Explain your answer from #4




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