Qwizdom Grading (4% of your course grade) 1.Each correct answer = 2 points 2.Each incorrect answer or no answer = 1 3.Absent = 0 points Suppose there are 40 questions during the term. Some possibilities Points % value Perfect – all correct 80 4 Always come to class 40 – 80 2 – 4 Never attend class 0 0 Come half the time 20 – 40 1 – 2

3. The amount of heat necessary to raise the temperature of 1 gram of water by 1°C is referred to as the A. calorie B. kilocalorie C. British thermal unit D. joule

3. The correct answer is A, the calorie.

4. Which of the following is the smallest unit of heat energy? A. calorie B. kilocalorie C. Btu D. joule

4. 1 kcal = 1000 cal 1 kcal = 4186 J 1 cal = J 1 Btu = 252 cal So the answer is D, the joule. From smallest to largest: J, cal, Btu, kcal

5.A chunk of ice (T = -20°C) is added to a thermally insulated container of cold water (T = 0°C). What happens in the container? A.The ice melts until thermal equilibrium is established. B.The water cools down until thermal equilibrium is established. C.Some of the water freezes and the chunk of ice gets larger. D. none of the above

5. The correct answer is C, some of the water freezes and the chunk of ice gets larger. The final temperature must be between 0 and -20°C. So more ice forms.

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