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WACE Stuff => Science => Mathematics/Science/Technology => WACE => Physics => Topic started by: memeningful on October 29, 2016, 10:20:40 pm

Title: memeningful's back and better with another question, this time for Physics!
Post by: memeningful on October 29, 2016, 10:20:40 pm
see that song reference I just did? xD anyway

I would like some help with this question

A nail is heated in a bunsen burner flame and is about to be dropped into a beaker of water at room temperature.

A) Which of the two substances (nail or water) would you expect to initially have:

i) the highest internal energy

ii) the highest average kinetic energy

thanks :)
Title: Re: memeningful's back and better with another question, this time for Physics!
Post by: jamonwindeyer on October 30, 2016, 12:03:28 am
Quote from: memeningful on October 29, 2016, 10:20:40 pm
see that song reference I just did? xD anyway

I would like some help with this question

A nail is heated in a bunsen burner flame and is about to be dropped into a beaker of water at room temperature.

A) Which of the two substances (nail or water) would you expect to initially have:

i) the highest internal energy

ii) the highest average kinetic energy

thanks :)

Hey! Welcome back ;)

Well we'd expect the nail to have the higher internal energy, since it has a higher temperature. Internal energy (unless it's stored chemical energy) is just heat! ;D

The average kinetic energy I'd say they are the same? They both start from rest BEFORE it is dropped, so I'd want to say they both have no kinetic energy before it is dropped! Once the nail drops though, it is moving, and so has the highest average kinetic energy :)

Feel free to come back and ask me if you need any follow up! And of course send any other questions our way ;D
Title: Re: memeningful's back and better with another question, this time for Physics!
Post by: memeningful on October 30, 2016, 01:26:42 pm
Quote from: jamonwindeyer on October 30, 2016, 12:03:28 am
Hey! Welcome back ;)

Well we'd expect the nail to have the higher internal energy, since it has a higher temperature. Internal energy (unless it's stored chemical energy) is just heat! ;D

The average kinetic energy I'd say they are the same? They both start from rest BEFORE it is dropped, so I'd want to say they both have no kinetic energy before it is dropped! Once the nail drops though, it is moving, and so has the highest average kinetic energy :)

Feel free to come back and ask me if you need any follow up! And of course send any other questions our way ;D

I've asked several people this and they all say it is the nail, but the book says it's water for the internal energy. The book says it's the nail that has the highest average kinetic energy
Title: Re: memeningful's back and better with another question, this time for Physics!
Post by: Sanaz on October 30, 2016, 01:28:39 pm
Is this from an option or a core topic?
Title: Re: memeningful's back and better with another question, this time for Physics!
Post by: Syndicate on October 30, 2016, 02:05:59 pm
Quote from: memeningful on October 30, 2016, 01:26:42 pm
I've asked several people this and they all say it is the nail, but the book says it's water for the internal energy. The book says it's the nail that has the highest average kinetic energy

Yes it is the water, since it is available in a great amount than compared to the mass of the nail. The nail has the highest average kinetic energy, since it is hotter than the water.
Title: Re: memeningful's back and better with another question, this time for Physics!
Post by: jamonwindeyer on October 30, 2016, 02:12:11 pm
Quote from: Sanaz on October 30, 2016, 01:28:39 pm
Is this from an option or a core topic?

This is WACE Physics (Western Australia) ;D

Quote from: Syndicate on October 30, 2016, 02:05:59 pm
Yes it is the water, since it is available in a great amount than compared to the mass of the nail. The nail has the highest average kinetic energy, since it is hotter than the water.

Hmm, I'm not sure about the water, but kinetic energy is energy possessed by bodies in motion (or is it something else in this context?)

Edit: Ahh, we're talking about substances. Kinetic energy of the molecules. Gotcha ;D