# AP Physics 2: 2.1 Probability and Systems

AP Physics 2: 2.1 Probability and Systems. During which of the following sequences is the energy change equal to zero?

 AP Physics 2 Probability and Systems Language English Language Science Practice 1 Using representations and models

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00:17

pressure volume diagram Right here Here we go The path

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from point c to point a is an ice Oh

00:23

thermal expansion and the number of molecules is such that

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the number of molecules times bowl timmons constant equals the

00:30

number of malls times the gas constant which also equals

00:33

one jule per kilogram During which of the following sequences

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is the energy change equal to zero There you go

00:41

Pointing at point b b c c a and here's

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a potential answers Yeah we're on the numeral time Yeah

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That's what i got right So we're talking about a

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change in energy here being a change in temperature The

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equation for the ideal gas law is pressure times Volume

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equals the number of moles times the gas constant times

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temperature The number of moles in the gas constant will

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stay the same here After all we're not taking any

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gas away and the gas constant is well constant So

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in order for the temperature not change in the product

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on the left side of the equation has remained the

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same Let's Look at this diagram again Moving from a

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to b means the volume will change but the pressure

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will stay the same and moving from b to c

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means the pressure will change but the volume will remain

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stable Neither of these scenarios the pv side of the

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equation real result in a change of temperature But in

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the change from c t es the pressure lowers the

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volume increases The left side of the equation will remain

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the same and the temperature energy won't change So the

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correct answer is c in a pressure volume equation the

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variables are dependent on each other So if one part

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changes other parts will change too Just like if we

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eat less our stomach pressure reduces as does our happiness 00:01:53.502 --> [endTime] But that's not a trade we're willing to make