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Q. Place a 1 kg block of iron at 40 degrees C into a kg of water at 20 degrees C and the final temp will be: More than 30 degrees C, Less than 30 degrees C, At or Around 30 degrees C.

I felt it would be At or Around 30 degrees C, because I tried to do an equation where I have 1(40 - T) = 1(T - 20), giving me 60 = 2T, giving me 30. But I don't really know if that's right. I don't know where I got the equation from...

Q. There's a span of steel 1.3km long, how long would it get if its temp was raised 15 degrees C. Using the formula Delta L = L(sub nought) alpha Delta T, which was then substituted to read (1300m) (11 x 10^-6/degrees C)(15 degrees C) = 0.21 meters.

I can't follow that. I can't follow the 11 x 1/10000000 part. Can't make it come out right with a number like that hanging around.

Any help appreciated. T minus 12 hours to the Big Test.

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# Homework Help: Expanding Steel, Can't Follow Equation

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