Test 1

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Test 1
Physical Science PHS 101
Beiser Chapter 1, 2, 3, 5
452 South Anderson Road Rock Hill, SC
29730 www.yorktech.com
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Scientific Method

• Physics - Motion Energy
• Physics - Electricity, Magnetism Optics
• Chemistry
• Meteorology
• Geology
• Astronomy

Tiger got to hunt, Bird got to fly Man got to
sit and wonder, "Why, why, why?"Tiger got to
sleep, Bird got to land Man got to tell
himself he understand.    - Kurt Vonnegut
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Chapter 1

• Physical Quantities

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Scientific Notation

• Good for very big or very small numbers.

300,000,000 3 x 100,000,000 3 x 10 x
10 x 10 x 10 x 10 x 10 x 10 x 10 3 x
108 0.0000052 5.2 1,000,000 5.2 x
10-6
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Unit Conversions
Since 3 ft 1 yd
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Unit Conversions
Since 5280 ft 1 mi and 1 m 3.28 ft
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Metric Arrow
3.72 dkm 3720 cm
1.5 m 1500 mm
1.5 m .015 hm
1200 cm 12 m
1655 dm .1655 km
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Vector Addition
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1.27
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Chapter 2

• Motion in a Straight Line

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Velocity
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Velocity Examples

• 1) If a person walks 15 miles in 3 hours, what is
  her average velocity? 
•  2) If a car travels at a velocity of 2 m/s for
  30 seconds, how far did it go?
•  3) If I travel 175 miles at 70 miles per hour,
  how long will it take?
• 4) If a plane travels north at 120 mph for 3 hr
  and then turns and flies west at 100 mph for 2
  hr, how far away from its starting point is it? 

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Acceleration
A change in speed in time

• acceleration due to gravity g 9.8 m/s2 32
  ft/s2

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Acceleration Examples

• 5) If my car is stopped at a light and then
  speeds up to 4 m/s in 2 s, find the acceleration.
• 6) If I'm traveling 6 m/s and step on the brakes
  to slow down to 2 m/s in 8 s,  find the
  acceleration.

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Freefall
   
If you drop a rock from the top of a building.. after 1, 2,3 and 4 seconds 7) how fast will it be moving?    8) how far will it have fallen?   (ignore air resistance) Time (s) Velocity (m/s) Distance (m)
If you drop a rock from the top of a building.. after 1, 2,3 and 4 seconds 7) how fast will it be moving?    8) how far will it have fallen?   (ignore air resistance) 1 s 9.8 m/s 4.9 m
If you drop a rock from the top of a building.. after 1, 2,3 and 4 seconds 7) how fast will it be moving?    8) how far will it have fallen?   (ignore air resistance) 2 s 19.6 m/s 19.6 m
If you drop a rock from the top of a building.. after 1, 2,3 and 4 seconds 7) how fast will it be moving?    8) how far will it have fallen?   (ignore air resistance) 3 s 29.4 m/s 44.1 m
If you drop a rock from the top of a building.. after 1, 2,3 and 4 seconds 7) how fast will it be moving?    8) how far will it have fallen?   (ignore air resistance) 4 s 39.2 m/s 784 m
     
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Chapter 3

• The Laws of Motion

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Newtons First Law

• 1st Law A body at rest will stay at rest a
  body in motion will stay in linear motion at
  constant velocity until a net force acts on it.

V
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Newtons Second Law

• 2nd Law A net force on a mass causes an
  acceleration.

F ma
a
F
m
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Newtons Third Law

• 3rd Law Every action (force) has an equal but
  opposite reaction.

Table pushes up on box.
Weight of box pushes down on table.
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Weight Mass

• Mass is how much stuff something has.
• Weight is how much gravity pulls on the stuff.

Object on Earth
Same object in space
No gravity to pull on mass. Object has same mass,
but no weight.
Gravity pulls on mass. Object has mass weight.
Mass Weight
Metric Kg Newton
British slug Pound
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Chapter 5

• Energy

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Work
F is force, s is distance m is mass g is gravity

• Using a force to move an object
• W Fs  mgs

Measured in kg m2/s2 J (metric) or ft lbs
(English)
Ex How much work does it take to lift a 200 kg
box 3 m into the air? W mgh (200 kg)(9.8
m/s2)(3 m) 5880 J
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Power

• The rate of work or how fast work gets done
• Ex How much power does it take to lift a 200 kg
  box 3 m into the air in 30s,

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Power Lifting Box
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Lifting Box English Units
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Kinetic Energy

• The energy of a moving object
• (m is mass of the object, v is the velocity)
• Ex Calculate the kinetic energy of a car that
  has a mass of 1500 kg moving at a speed of 5 m/s.
• KE ½ m v2 ½ (1500 kg)(5 m/s)2 18,750 J

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Potential Energy

• The energy an object develops by being raised to
  a height
• PE mgh  
• (m is mass, g 9.8 m/s, h is height)
• EX Calculate the potential energy of a book that
  has a mass of 5 kg that is 2 m above the ground.
• PE mgh (5 kg)(9.8 m/s2)(2 m) 98 J

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PE Example
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Conservation of Energy

• The total energy of a system cannot change unless
  energy is taken from or added to the system.  At
  any two points, 1 and 2
• PE1 KE1 PE2 KE2

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Cons. Of Energy
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Cons.of Energy Ex.
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Energy Summary
Name Symbol Description Formula Units
Kinetic Energy KE Energy of moving object KE ½ m v2 Joules or Ft lbs
Potential Energy PE Energy of raised object PE mgh Joules or Ft lbs
Work W Force moving an object W Fd Joules or Ft lbs
Conservation of energy Energy is constant W PE KE Joules or Ft lbs
Power P Speed of work P W / t Watts or Ft lbs / s or hp
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Test 1 Equations
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2.24
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2.38
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3.8
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3.29
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3.35
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3.39
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