1. Chapter 13 Motion

2. Table of Contents 13-1 What are Motion and Speed?
13-2 What are velocity and acceleration?
13-3 What is momentum?
13-4 What is Newton’s First Law of Motion?
13-5 What is Newton’s Second Law of Motion?
13-6 What is Newton’s Third Law of Motion?

3. 13-1 What are Motion and Speed?
Motion-a change in the position relative to
some fixed object or place
 Speed = distance  time
Example; Boat traveling 120 km in 4 hours has
what speed?
To calculate speed, distance or time, solve
algebraically or use the triangle method:
v x t d
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4. Answer Speed = 120 km  4 hours Speed = 30 km/hr Triangle Method…
V x 4 hr
120 km
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5. 13-1 What are Motion and Speed? (continued)
Average Speed = total distance  time
Velocity- the same as speed, but also tells the direction (same formula) example;90 km/hour west (velocity) 90 km/hour (speed)
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6. 13-2 What are velocity and acceleration?
Acceleration – a change in velocity
Formula for acceleration:
Acceleration = change in velocity  time
Acceleration = final velocity - initial velocity
Time
A = Vf - Vi T
If the object is at rest before it accelerates, the initial velocity is 0. If the object comes to a stop, the final velocity is 0.
-Sometimes acceleration can be negative…. This is called deceleration.
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7. 13-2 What are velocity and acceleration? (continued)
Example; If a wolf is sitting next to a log and chases after a turkey, which took 10 seconds……what was his acceleration if when he caught the turkey the wolf’s velocity was
28 m/sec.?
A = 28 m/sec - 0
10 sec
A =2.8 m/sec/sec or m/sec2
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8. 13-3 What is momentum? Momentum = mass x velocity
Example; If a football player is running 8 m/sec and has a mass of 300 kg, what is his momentum?
Answer = kg-m/sec
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9. 13-3 What is momentum? (continued)
Law of Conservation of Momentum- in any isolated system, momentum can be transferred but cannot be lost.
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10. 13-4 What is Newton’s First Law of Motion?
An object in motion will remain in motion, an object at rest will remain at rest unless acted on by an outside force. Also known as inertia.
Examples; moving car taking a sharp turn, roller coaster at top of hill, person in car accident without seatbelt on, pulling table cloth off with table set.
Video of 1st Law of Motion
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11. 13-5 What is Newton’s Second Law of Motion?
Force = Mass x Acceleration
F = M x A
One Newton (N) is the force needed to accelerate
a one kg mass to an acceleration of 1 m/sec/sec
Example;
If there were no friction, what force would be needed to accelerate a 5-kilogram mass 20 m/sec/sec?
Answer =
100 N
Video of 2nd Law of Motion
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12. 13-6 What is Newton’s Third Law of Motion?
For every action there is an equal and opposite reaction.
Examples; rocket blasting off, balloon being released, tennis racket and ball
Video of 3rd Law of Motion
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