Let the cold water go up x degrees.
Let the hot water go down 100 - x degrees.
The formula for heat exchange is m*c*delta t
Givens
Ice
deltat = x
m = 0.50 kg
c = 4.18
Hot water
deltat = 100 - x
m = 1.5 kg
c = 4.18
Formula
The heat up = heat down
0.50 * c * x = 1.5 * c * (100 - x) Divide both sides by c
Solution
0.50 *x = 1.5*(100 - x) Remove the brackets.
0.5x = 150 - 1.5x Add 1.5x to both sides.
0.5x + 1.5x = 150 - 1.5x + 1.5x Combine like terms
2x = 150 Divide by 2
x = 75
Answer
A
Well, first of all, there's no such thing as "fully charged" for a capacitor.
A capacitor has a "maximum working voltage", because of mechanical
or chemical reasons, just like a car has a maximum safe speed. But
anywhere below that, cars and capacitors do their jobs just fine, without
any risk of failing.
So we have a capacitor that has some charge on it, and therefore some
voltage across it. From the list of choices above . . .
<span>-- Both plates have the same amount of charge.
Yes. And both plates have opposite TYPES of charge.
One plate is loaded with electrons and is negatively charged.
The other plate is missing electrons and is positively charged.
-- There is a potential difference between the plates.
Yes. That's the "voltage" mentioned earlier.
It's a measure of how badly the extra electrons want to jump
from the negative plate to the positive plate.
-- Electric potential energy is stored.
Yes. It's the energy that had to be put into the capacitor
to move electrons away from one plate and cram them
onto the other plate.
</span>
Before we dive into how electricity is used around the home it is worth putting household electricity use in perspective.
Household electricity use generally makes up about a third of total electricity consumption in most developed nations. Using data from the European Union we can give an example of how electricity demand is split among different sectors.
<span>
Read more at http://shrinkthatfootprint.com/how-do-we-use-electricity#DfE5FuAPpy6Z5TBH.99
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