Quiz 3

Math 152–Spring 2016
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Quiz 3
Sections 7.3, 7.4
Directions: You may not use your class notes, calculator, cell phone or any other electronic devices. You
must show all your work to receive credit. Your grade will be determined not only by your final answer, but
also the correctness of your work.
Section Number:
1. (6 points) Use the method of cylindrical shells to find the volume generated by rotating the region
bounded by y = x2 , y = 0, x = 1, and x = 2 about x = 4.
2. (6 points) A force of 20 lbs is required to hold a spring stretched 4 in. beyond its natural length. How
much work W is done in stretching it from its natural length to 8 in. beyond its natural length?
Math 152–Spring 2016
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3. (6 points) The aquarium shown below is full of water. Find the work needed to pump all of the water
out of the aquarium. Use 62.5 lb/ft3 for the weight density of water. Assume that a = 3 ft, b = 2 ft,
c = 6 ft, and d = 1 ft. You may write your answer as a multiple of 62.5 without multiplying it out.