Internal energy (U) of an isolated system

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rkang00
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Internal energy (U) of an isolated system

Postby rkang00 » Tue Feb 12, 2019 2:50 pm

If a system is isolated with + amount of energy, will it there be no change even after time passes?

julia_lok_2K
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Re: Internal energy (U) of an isolated system

Postby julia_lok_2K » Tue Feb 12, 2019 3:04 pm

There wouldn't be any change after time passes because it's isolated--it won't be able to exchange energy or matter with its surroundings.

Neil Hsu 2A
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Re: Internal energy (U) of an isolated system

Postby Neil Hsu 2A » Wed Feb 13, 2019 7:36 pm

The First Law of Thermodynamics states that the change in internal energy of an isolated system is 0. So to answer your question, if a system had, let's say +5kJ, after any amount of time, it will still have +5kJ.

AdityaGuru1H
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Re: Internal energy (U) of an isolated system

Postby AdityaGuru1H » Wed Feb 13, 2019 8:32 pm

how we measure if a system is open, closed, or isolated is if it is able to transfer heat or work with the surroundings which is also how we measure internal energy. In the case of an isolated system it is not able to transfer either so w and q are both 0 which makes deltaU = 0

Athena L 1B
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Re: Internal energy (U) of an isolated system

Postby Athena L 1B » Thu Feb 14, 2019 4:27 pm

Closed systems can transfer only energy, and open systems can transfer energy and matter

EllaBerry
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Re: Internal energy (U) of an isolated system

Postby EllaBerry » Fri Feb 15, 2019 5:16 pm

An isolated system will never exchange energy regardless of how much time passes.

Henry Dudley 1G
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Re: Internal energy (U) of an isolated system

Postby Henry Dudley 1G » Sat Feb 16, 2019 8:39 pm

rkang00 wrote:If a system is isolated with + amount of energy, will it there be no change even after time passes?


There will be no change regardless of the amount of time passed. However, this is not the case for open and closed systems.

chrisavalos-2L
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Re: Internal energy (U) of an isolated system

Postby chrisavalos-2L » Sat Feb 16, 2019 11:48 pm

There would be no change because there will be no interactions with the surroundings, therefore no energy lost or energy gained so delta U will be zero, and the U itself will be the same.

Kyither Min 2K
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Re: Internal energy (U) of an isolated system

Postby Kyither Min 2K » Mon Feb 18, 2019 7:48 pm

The internal energy of the system would not change as an isolated system doesn't exchange energy or matter with it's surroundings and based off the conservation of energy theory, if energy isn't used or exchanged, the energy will stay constant.

Jonathan Pai 2I
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Re: Internal energy (U) of an isolated system

Postby Jonathan Pai 2I » Mon Feb 18, 2019 8:33 pm

isolated system transfers no matter or energy, so deltaU is 0, however U can have a specific value.

RachelCheung1A
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Re: Internal energy (U) of an isolated system

Postby RachelCheung1A » Mon Feb 18, 2019 11:14 pm

In an isolated system, there is no exchange of energy with surroundings and therefore the internal energy stays the same and delta U is 0

005115864
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Re: Internal energy (U) of an isolated system

Postby 005115864 » Mon Feb 18, 2019 11:32 pm

Internal energy does not change in an isolated system since it isn't able to exchange heat with its surroundings!

Hadji Yono-Cruz 2L
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Joined: Fri Sep 28, 2018 12:26 am

Re: Internal energy (U) of an isolated system

Postby Hadji Yono-Cruz 2L » Sun Feb 24, 2019 12:48 am

There would not be change because matter and energy is not exchanged between an isolated system and its surroundings.

Luis_Yepez_1F
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Re: Internal energy (U) of an isolated system

Postby Luis_Yepez_1F » Sun Feb 24, 2019 6:47 pm

There is no change in energy within a closed system. Since energy can neither leave or enter the system.

Pritish Patil 1K
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Re: Internal energy (U) of an isolated system

Postby Pritish Patil 1K » Thu Mar 14, 2019 12:55 pm

The amount of energy would be the same as it is an isolated system.

Rhea Churi 4K
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Re: Internal energy (U) of an isolated system

Postby Rhea Churi 4K » Thu Mar 14, 2019 1:24 pm

An isolated system cannot exchange matter or energy so there is no change.

Nghi Nguyen 2L
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Re: Internal energy (U) of an isolated system

Postby Nghi Nguyen 2L » Fri Mar 15, 2019 9:50 pm

in an isolated system there is neither an exchange of energy nor matter

Rehan Chinoy 1K
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Re: Internal energy (U) of an isolated system

Postby Rehan Chinoy 1K » Sat Mar 16, 2019 4:32 pm

There was a question like this on the midterm -- if an isolated system has an internal energy of +5 J, then after 100 years it will have an internal energy of +5 J.


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