Negative work


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Rita Chen 1B
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Negative work

Postby Rita Chen 1B » Wed Feb 12, 2020 9:07 am

When is work negative?

Daniel Toscano 1L
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Re: Negative work

Postby Daniel Toscano 1L » Wed Feb 12, 2020 9:07 am

When a system does work

Jessica Li 4F
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Re: Negative work

Postby Jessica Li 4F » Wed Feb 12, 2020 2:51 pm

Work is negative when a system does work, which means that it expands. If you do work, you lose energy, so it is negative. On the other hand, work is being done on the system when it is compressed. Think of it as the system can expand by itself, but you have to do something to the system to compress it.

Matthew Tsai 2H
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Re: Negative work

Postby Matthew Tsai 2H » Sat Feb 15, 2020 11:54 am

When a system does work, it loses energy in the process, so the value for w is negative.

Jacob Motawakel
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Re: Negative work

Postby Jacob Motawakel » Sat Feb 15, 2020 3:07 pm

A system's work is negative when that system does work, Work is positive for a system if work is done on that system.

Callum Guo 1H
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Re: Negative work

Postby Callum Guo 1H » Sat Feb 15, 2020 3:17 pm

when your system does work. so in this class, most of the time its when a gas expands.

Amanda Mei 1B
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Re: Negative work

Postby Amanda Mei 1B » Sat Feb 15, 2020 3:48 pm

When a system pushes against an external force (pressure), it loses energy and thus work is negative. Usually this causes volume to expand.

HuyHa_2H
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Re: Negative work

Postby HuyHa_2H » Sat Feb 15, 2020 5:28 pm

Work is negative when a system is doing work because that's what it loses hence the negative. Conversely, it's positive if something else is doing work on the system.

Kayli Choy 2F
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Re: Negative work

Postby Kayli Choy 2F » Sat Feb 15, 2020 9:11 pm

Work = -(pressure)(FinalVolume - InitialVolume). Therefore, if your final volume is greater than your initial volume (gas expands) then your change in volume will be positive, so this is why work will be negative. Additionally if your initial volume is greater than your final volume (gas is compressed), then your change in volume will be negative, so work will be positive.

Matthew Chan 1B
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Re: Negative work

Postby Matthew Chan 1B » Sun Feb 16, 2020 9:56 pm

Work is negative when the system does work itself, which makes sense since the system is "losing" work/energy, which makes sense why it would be negative.

Nikki Razal 1L
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Re: Negative work

Postby Nikki Razal 1L » Sun Feb 16, 2020 10:00 pm

when a system does work, it is by a negative sign

CalvinTNguyen2D
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Re: Negative work

Postby CalvinTNguyen2D » Sun Feb 23, 2020 11:41 pm

Work, as viewed through the lenses of chemistry, is positive when it is being done ON the system. Therefore, work is negative when the system itself is doing work on the surroundings.

lauraxie2e
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Re: Negative work

Postby lauraxie2e » Mon Feb 24, 2020 10:46 am

when the system does work on the surroundings

Elizabeth Harty 1A
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Re: Negative work

Postby Elizabeth Harty 1A » Mon Feb 24, 2020 11:23 am

When a system does work the value is negative

Ian Morris 3C
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Re: Negative work

Postby Ian Morris 3C » Tue Feb 25, 2020 8:56 pm

if a system is negative, then it just has done work


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