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ROxy

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Formula
« on: November 24, 2004, 08:08:12 PM »
What formula do I use if I want to calculate how much energy is absorbed by water?

Donaldson Tan

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Re:Formula
« Reply #1 on: November 24, 2004, 08:30:50 PM »
Q = mc.dT

Q: heat absorbed
m: mass of water
c: specific heat capacity of water
dT: change in temperature
"Say you're in a [chemical] plant and there's a snake on the floor. What are you going to do? Call a consultant? Get a meeting together to talk about which color is the snake? Employees should do one thing: walk over there and you step on the friggin� snake." - Jean-Pierre Garnier, CEO of Glaxosmithkline, June 2006

ROxy

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Re:Formula
« Reply #2 on: November 24, 2004, 08:53:38 PM »
Q = mc.dT

Q: heat absorbed
m: mass of water
c: specific heat capacity of water
dT: change in temperature

Can iuse the same formula to find the amount  per gram of fuel burned?

ssssss

• Guest
Re:Formula
« Reply #3 on: November 25, 2004, 07:58:22 AM »
Can iuse the same formula to find the amount  per gram of fuel burned?

No

Donaldson Tan

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Re:Formula
« Reply #4 on: November 25, 2004, 05:44:38 PM »
Q = mc.dT is applicable for physical processes. eg. transfer of heat to water.

Q = mc.dT is only applicable for burning fuel for this case:

1. burn 200g of fuel
2. heat evolved is used to heat water
3. all heat evolved from burning fuel channels to the water. [assumption]
4. water remains in liquid state.

heat evolved for burning 200g of fuel
= heat absorbed by water
= mc.dT where m: mass of water, c: specific heat capacity, dT: change in temperature.
"Say you're in a [chemical] plant and there's a snake on the floor. What are you going to do? Call a consultant? Get a meeting together to talk about which color is the snake? Employees should do one thing: walk over there and you step on the friggin� snake." - Jean-Pierre Garnier, CEO of Glaxosmithkline, June 2006