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An old Biblical story tells of David, a small warrior engaged inman-to-man combat with Goliath, a much larger adversary. In thestory, David uses a sling to increase the speed of a projectile (inthis case a rock), striking Goliath in the forehead and killinghim. The type of sling often used in such combat consists of a longstrip of cloth with a pouch halfway down its length. The rock ispositioned in the pouch, with the warrior holding both ends of thesling. By whirling the sling in a horizontal* circle, a warrior canrelease one end of the sling, therefore allowing the projectile tofly in a straight line at high speed. In this problem, we willassume that the sling, when unfolded, was roughly 5.12 feet intotal length. We will also assume the rock weighed a half a pound.If David whirled the sling to the point where the sling subtendedan angle of θ = 3.93o with the horizontal, with what speed did therock strike Goliath? (Assume no air friction and that the drop inheight due to gravity is minimal.)

speed rock struck Goliath = ______ mph

A typical break shot in pool (the opening shot) is about 20 mphwith a ball that is about half the weight of the rock in the story.Considering this, what impact do you think a half-pound rocktraveling at the above calculated speed would have on someone ifstruck in the forehead?

-a- The impact would hurt a little but would likely not causeany injury.

-b- The impact would likely cause serious injury.

Suppose David had missed. How far would the rock travel beforestriking the ground if David released it from a height of 4.25 ft?(Assume no air friction.)