Units and Measurement. A) SI Units, Scientific Notation, Measurement, Accuracy, Precision, Error.
Fundamental Quantities and Units
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description
Fundamental Quantities and Units. Fundamental QuantityMKS Unit * Length(Meters) * Mass(Kilograms) * Time(Seconds). Motion. Motion. The symbol “ Δ ” means “Change in”. Motion. The symbol “ Δ ” means “Change in”. The speed changes by 4 m/sec every second. - PowerPoint PPT Presentation
Transcript of Fundamental Quantities and Units
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Fundamental Quantities and Units
Fundamental Quantity MKS Unit
* Length (Meters)
* Mass (Kilograms)
* Time (Seconds)
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Motion
Quantity Symbol Definition Units
Distance d m
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Motion
The symbol “Δ” means “Change in”
Quantity Symbol Definition Units
Distance d m
Speed v d/Δt m/s
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Motion
The symbol “Δ” means “Change in”
Quantity Symbol Definition Units
Distance d m
Speed v d/Δt m/s
Acceleration a Δv/Δt m/s2
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Part 2, B: MOTION
Derived Quantity - Acceleration
An object is moving with a speed of 3 m/secand accelerates at 4 m/sec . What is itsspeed after 1 sec, 2 sec, etc?
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Part 2, B: MOTION
Derived Quantity - Acceleration
An object is moving with a speed of 3 m/secand accelerates at 4 m/sec . What is itsspeed after 1 sec, 2 sec, etc?
The speed changes by 4 m/sec every second
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Part 2, B: MOTION
Derived Quantity - Acceleration
An object is moving with a speed of 3 m/secand accelerates at 4 m/sec . What is itsspeed after 1 sec, 2 sec, etc?
After 1 sec v = 7 m/sec
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Part 2, B: MOTION
Derived Quantity - Acceleration
An object is moving with a speed of 3 m/secand accelerates at 4 m/sec . What is itsspeed after 1 sec, 2 sec, etc?
After 1 sec v = 7 m/sec
After 2 sec v = 11 m/sec
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Part 2, B: MOTION
Derived Quantity - Acceleration
An object is moving with a speed of 3 m/secand accelerates at 4 m/sec . What is itsspeed after 1 sec, 2 sec, etc?
After 1 sec v = 7 m/sec
After 2 sec v = 11 m/sec
After 3 sec v = 15 m/sec
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Motion
Relationships
If a = 0
d = vt
If a ≠ 0
d = ½ a t2
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Part 2, B: MOTION
Derived Quantity - Acceleration
Observation (Galileo): All objects in freefall near the surface of the earth accelerateat 9.8 m/sec toward the surface of theearth.
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Part 2, B: MOTION
Derived Quantity - Acceleration
Observation (Galileo): All objects in freefall near the surface of the earth accelerateat 9.8 m/sec toward the surface of theearth.
Free Fall: Any motion for which the onlyinfluence is gravity.
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Motion
An object is thrown vertically upward from the surface of the earth in the absence of air resistance.
Note: this can be accomplished, for example, in an experimental facility from which the atmosphere has been removed.
1. What is the acceleration of the object on its way up?
2. What is the acceleration of the object on its way down?
3. If the object is thrown vertically, it will stop at the highest point in its motion. What is the acceleration of the object at the moment that it stops?
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Motion
Air Hockey
There is no friction between the puck and the table surface
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Motion
Free Fall Tower
Drop distance - dd
y Height above base - y
100 m
Assumption: No air resistance
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Motion
1. Assume the air hockey puck moves with an initial speed of 10 m/s. What is its position (assume it starts a 0 m) after 1 s, 2 s, 3 s, 4 s and 5 s?
2. Assume the Free Fall Tower is 100 m high. What is the drop distance and the height above the base after 1 s, 2 s, 3 s, 4 s and 5 s? Assume g = 10 m/s2 .
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Motion
Can be a combination
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Motion
Can be a combination
d = ½ a t2
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Motion
Can be a combination
d = ½ a t2
d = v t
