Solar Power Pond Pump

Doris Said:

Help with science math hw please? (7questions)?

We Answered:

I'll choose #2, since it's pretty easy for me.

There's an equation, I don't know if you know it, but it's expressed as

Q = (m)(?T)(c)

Q = Heat released/absorbed
m = Mass of substance (IN GRAMS)
?T = Change in temperature
c = Specific heat of substance

You have Q, m, and ?T. Setting up the equation, you have something like:

9,000 = (500 g)(10)(x)

My calculated specific heat is 1.8 J/g°C.

This is a reasonable answer, as water's specific heat is about 4.184 J/g°C. Metals tend to have low specific heats compared to water.

Dean Said:

Lost in the physics world... please help me.?

We Answered:

For the first two:
You could either go to an online conversion site if you're lazy, or you can use this formula to convert from degC to degF:
degF = (9/5)*degC + 32. To go the opposite way, solve for degC.

The next few questions can be solved by using Q=mc(delta)T where (delta)T is the change in temperature, "c" is the specific heat capacity of the medium, m is the mass, and Q is the total energy.

As for the last few, well, here's my attempt at giving you answers:
"Calculate Solar Radiation". If the house is 10mX10m, that's 100 sq.m. So, your equation would look like:
200 W/sqM * 100 sq.M = 20 000 W = 20kW. That is assuming a perfect rectangle and that the house is directly underneath the Sun, with no other obstacles in the way.

The other ones I'm not going to answer for you, as I pretty much did your whole assignment already.

Good luck

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