|THE INTERNET PLASMA PHYSICS EDUCATION EXPERIENCE|
Tea TimeYour Aunt Matilda is staying with you and is bedridden upstairs. Dad asked you to help her out while he's at work and now she wants some tea. Trouble is the neighborhood soccer game is tied and you don't want to have to come inside more than one more time (especially when you have to take off your muddy cleats).
You know Aunt Matilda hates to have her tea bag boiled (like last time) but you could put the tea bag in a cup of water, set the microwave to almost boil it (Dad gave you careful instructions on handling boiling water and on using the microwave), and come back 5 minutes later and it would be steeped to perfection. You flip open your science book and see that the "specific heat" (the amount of energy associated with temperature changes) of water is 4180 Joules per kilogram - degrees Celsius (what's with these foreign units?). You know your microwave is 750 Watts (and you remember that a Watt is 1 Joule per second). Let's see, the water is a little cool from the tap, say 15 degrees Celsius and, of course, water boils at 100 degrees Celsius. Uh huh, uh huh, but how many kilograms does a stupid cup of water weigh? (You hear the other team cheer wildly outside.) Let's see, a liter is about a quart and there are two pints in a quart and two cups in a pint (and of course a milliliter of water weighs about 1 gram), so let's write the equation so the units cancel leaving only seconds in the numerator, and the answer is _______________ seconds. <send your answer to email@example.com for the verification.>
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