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### Closed Systems

Posted: Sun Feb 02, 2020 2:52 pm
How can you change the energy in a closed system? And does it differ with isolated systems?

### Re: Closed Systems

Posted: Sun Feb 02, 2020 2:58 pm
Emily Lo 1J wrote:How can you change the energy in a closed system? And does it differ with isolated systems?

Quoting this because I want to see the replies that it gets :)

### Re: Closed Systems

Posted: Sun Feb 02, 2020 3:01 pm
In a closed system, you can change the energy by adding heat and/or doing work on the system. I am less certain with the isolated system, but I am pretty sure there should be no net change in the total energy of the system.

### Re: Closed Systems

Posted: Sun Feb 02, 2020 3:03 pm
On a closed system, you can add energy by adding it to the entire system, which is different from an open system where you can pick where to add work/energy, or an isolated system where you can't add energy, I think.

### Re: Closed Systems

Posted: Sun Feb 02, 2020 4:02 pm
In a closed system, pressure can be applied.

### Re: Closed Systems

Posted: Mon Feb 03, 2020 1:22 pm
In a closed system, energy can be exchanged with surroundings, unlike an isolated system in which nothing can be exchanged with the surroundings. The energy of a closed system can be changed by heating/cooling or compression/expansion (i.e. compressing a piston).

### Re: Closed Systems

Posted: Mon Feb 03, 2020 5:30 pm
ΔU = q + w, so to change the energy of a closed system, you would heat it or do work on it.

### Re: Closed Systems

Posted: Mon Feb 03, 2020 5:36 pm
KBELTRAMI_1E wrote:
Emily Lo 1J wrote:How can you change the energy in a closed system? And does it differ with isolated systems?

Quoting this because I want to see the replies that it gets :)

I would assume you would add heat to change energy since the system is isolated.

### Re: Closed Systems

Posted: Mon Feb 03, 2020 6:13 pm
An example of changing energy of a closed system would be adding or removing heat, or compression/expansion. An isolated system cannot transfer energy with its environment.

### Re: Closed Systems

Posted: Mon Feb 03, 2020 7:30 pm
Heat transfer can occur in a closed system or work can be done via compression/expansion. We cannot add any substance in the system, but heat transfer can occur between the system and surroundings. Think of a cold ice pack as a closed system.

### Re: Closed Systems

Posted: Mon Feb 03, 2020 7:56 pm
in a closed system, you can change the energy by doing work/having work done on the system or by changing the temperature

### Re: Closed Systems

Posted: Mon Feb 03, 2020 7:56 pm
deltaU = q + w so you can change it by adding heat or doing work

### Re: Closed Systems

Posted: Fri Mar 13, 2020 10:05 am
Eva Zhao 4I wrote:In a closed system, energy can be exchanged with surroundings, unlike an isolated system in which nothing can be exchanged with the surroundings. The energy of a closed system can be changed by heating/cooling or compression/expansion (i.e. compressing a piston).