Name ______Date ______
Motion & Newton’s Laws: State Correlation 2c & 2f
I. MOTIONA. All matter is in ______motion
•Motion is any ______in position
•______motion is used to recognize a change in position by using a point of reference
•An object changes positions if it moves relative to a ______point
B. Measuring Motion
•______is the total length of the route an object travels when it moves
•______includes distance from the starting point to the stopping point and the direction traveled
•Ex. 40m 30m
40m
Distance = ______
Displacement = 40m ______
C. Speed
•______is the distance traveled divided by the time taken to travel the distance
•Formula: Speed = ______÷ ______(S=D/T)
•______: meters per second (m/s)
•Ex. In the 100m dash the fastest runner finished in 10s. S= 100m/10s= ______
•3 Types of Speed
•______is found by dividing the total distance by the total time taken to reach that distance
•Speeds can ______from instant to instant
•Ex. Walking in a crowded hallway
•______Speed is the speed of an object at a particular moment
•______Speed is when an object is moving at a steady rate throughout the entire distance
D. Practice Problem
•Calculate the Average Speed. Round to the nearest 0.1m/s
•A swimmer swam 100m in 56s. Answer:______
E. Graphing Motion
•Motion can be graphed on a ______graph
•Time on the ______axis
•Distance on the ______axis
•The ______the line on a distance-time graph, the ______the speed
•A horizontal line means no change in position, which makes the speed “zero” at anytime on the graph
F. Velocity
•Velocity is the ______of an object and the ______of its motion.
•Unit is same as ______, but includes direction
•10km/h ______
•Example: A hiker needs to know how far away the camp is & in what direction to determine the necessary velocity to get back to camp before nightfall
G. Acceleration
•Acceleration occurs when an object ______its motion (velocity changes)
•______- 50m/h to 60m/h (positive)
•______– 45m/h to 40m/h (negative)
•Acceleration is in the ______direction of the motion
•______in direction – north to east
•Basket ball thrown from the free-throw line
Can you think of examples of situations that have positive or negative acceleration? ______
H. Calculating Acceleration
•If an objects motion is in a ______line the acceleration can be calculated using this formula:
(A)Acceleration = final speed(sf) – initial speed(si)
Time(t)
•Unit for acceleration is ______
•Calculate the acceleration of a bus whose speed changes from 6m/s to 12m/s over a period of 3s.
•Initial speed: ______m/s
•Final speed: ______m/s
•Time: ______s
I. Practice Problems
1.A train’s velocity increases from 7m/s to 18m/s over a period of 120s. ______
2.Jack was riding a bike in a straight line and speeded up from 4m/s to 6m/s in 5s. ______
3.Sarah slowed down from 4m/s to 2m/s in 5s as she walked her last lap on the track. ______
J. Graphing Acceleration
•Accelerated motion can be graphed by putting ______on the vertical axis and ______on the horizontal axis
K. Graphing Acceleration
•Practice Graphing- A sprinter had the following speeds at different times during a race: 0m/s at 0s, 4m/s at 2s, 7m/s at 4s, 10m/s at 6s, 12m/s at 8s, 10m/s at 10s and 10m/s at 12s. Plot this data on a speed-time graph and answer the following questions:
- During what interval is the acceleration positive?
- Negative?
- Is the acceleration ever zero? Explain.
II. Newton’s 3 Laws of Motion (2f)
A. What is a Force
•Force is defined as a ______or a ______
–Ex. Pushing a grocery cart or pulling a wagon
•______force is the ______of all forces acting on an object at the same time.
–Ex. Identify all the forces acting on a paper clip, sitting on a table, near a magnet.
______
B. Balanced verses Unbalance
•______occur when two or more forces exerted on an object cancel each other out causing ______in motion (no acceleration)
–Ex. Lean back to back with a partner with no motion or hold a book in your hand very still
•______occur when the combined forces acting on an object do not cancel each other out causing a ______in motion (acceleration)
–Ex. Push a chair with wheels or when someone wins tug-a-war
C. Decide if the situation is Balanced or Unbalanced
1.Push a box till it moves ______
2.Pedal a bike at a constant speed ______
3.Apply brakes to a bike in order to pop a wheelie ______
4.Push a car that never moves______
5.Two people push a box in opposite directions causing the box to go nowhere______
6.Two people push a box in opposite directions causing the box to slide slightly to the right _____
D. Newton’s first law
•2 parts
–An object will remain at ______until an unbalanced force is applied to the object
•Ex. Skateboard pushed in motion
–An object in motion will remain in ______at a ______rate until an unbalanced force is applied to the object
•Ex. Moon moves in a consistent pattern
•Known as the “______”
–Inertia is the tendency of an object to ______in its motion
•Ex. Applying breaks in a car and your body goes forward
E. Friction
•Friction is a force that ______between two touching surfaces or through air or water.
Friction ______down an object’s motion.
Friction produces ______and wares on objects
F. Newton’s 2nd Law
•Newton’s second law of motion ______force, acceleration, and mass
an object acted on by a force will ______in the ______of the force
acceleration ______net force divided by mass.
Ex. An empty skateboard verses a person standing on a skateboard: Which one will you have to push harder to go the same distance?
Formula: (a = fnet ÷ m) or (______)
Forces are measured in ______(N)
1N = 1kg x ______
G. Practice Newton’s 2nd law
•Suppose you pull a 10kg sled so that the net force on the sled is 5N. What is the acceleration of the sled? A = 5N ÷ 10kg = ______
•You throw a baseball with a mass of 10kg so it has an acceleration of 40m/s2. How much force did you exert on the baseball? Answer: ______
Making a connection: Explain the connection between motion, 1st law, & 2nd law. ______
H. Newton’s 3rd Law
•Newton’s third law of motion states that forces always act in ______but ______pairs called action/reaction forces
for every ______there is an equal and opposite reaction.
Bounce a ball on the ground or playing pool
•______forces are always the same size but are in opposite directions and act on different objects.
When the mass of one object is considerably larger than the mass of another object, the action-reaction force is not ______.
When you push a wall or walk on the earth.
I. Action/Reaction Forces
•When one object exerts a force on another object the 2nd object exerts the ______force on the 1st object
•Forces act on ______objects, so they do not cancel each other out
Underline the objects the action reaction force is being applied to
Action
•Wings push air down & back
•Hands push water back
•Foot pushes down and back on earth
•Rocket engine pushed gas molecules downward
The greater the mass the greater the ______
J. Which law?
1.Using an oar to move a canoe ______
2.Pushing a swing with more force to move your big brother than you did with your little sister______
3.A rock is sitting on a hill until you push it causing it to roll ______
Vocabulary: 1. motion, 2. speed, 3. acceleration, 4. velocity, 5. average speed, 6. constant speed, 7. force, 8. net force, 9. balanced force, 10. unbalanced force, 11. Newton’s first law, 12. Newton’s second law, 13. Newton’s third law, 14. inertia, 15. action/reaction force, 16. friction