Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f =...
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Transcript of Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f =...
![Page 1: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/1.jpg)
Potential Potential Energy & Energy Energy & Energy Conservation Conservation
![Page 2: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/2.jpg)
Work Done by Gravity 1Work Done by Gravity 1
Example 1: Drop ball
Yi = h
Yf = 0
mgS
y
x
Yi = h
Yf = 0
mgS
y
x
10
![Page 3: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/3.jpg)
Work Done by Gravity 2Work Done by Gravity 2
Example 2: Toss ball up
Yi = h
Yf = 0
mgS
y
x
13
![Page 4: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/4.jpg)
Work Done by Gravity 3Work Done by Gravity 3
Example 3: Slide block down incline
h
mgS
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![Page 5: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/5.jpg)
Example: roller coasterExample: roller coaster
20m 15m
8mA
C
B
D
VO=0
Find the velocity of the coaster at points A,B,C,D
![Page 6: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/6.jpg)
Example: roller coasterExample: roller coaster
20m 15m
8mA
C
B
D
VO=0
Find the velocity of the coaster at points A,B,C,D
![Page 7: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/7.jpg)
Example: roller coasterExample: roller coaster
20m 15m
8mA
C
B
D
VO=0
Car stops in 10m, what is the average force of friction?10m
![Page 8: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/8.jpg)
Example: blocks and pulleyExample: blocks and pulley
3kg
1kg1.5m
What is the velocity of the 3kg block right before is hits the ground?
![Page 9: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/9.jpg)
Power (Rate of Work)Power (Rate of Work)
P = W / t Units: Joules/Second = Watt
How much power does it take for a (70 kg) student to run up 5m high stairs in 7 seconds?
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![Page 10: Potential Energy & Energy Conservation. Work Done by Gravity 1 l Example 1: Drop ball Y i = h Y f = 0 mg S y x Y i = h Y f = 0 mg S y x 10.](https://reader036.fdocuments.net/reader036/viewer/2022062309/5697bf771a28abf838c81523/html5/thumbnails/10.jpg)
SummarySummaryConservative Forces
» Work is independent of path
» Define Potential Energy UUgravity = m g yUspring = ½ k x2
Work – Energy TheoremUKWnc
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