Stephanie M. answered • 04/24/15

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The general equation for distance traveled involves initial velocity v

_{i}, time t, and acceleration a:d = v

_{i}t +^{1}/_{2}at^{2}You've been given d = 230 feet, v

_{i}= 0 feet per second ("from rest"), and t = 5 seconds. Normally, in this type of problem, you'd use gravity as the acceleration. Instead, since acceleration is the only unknown left in the equation, we'll solve for a:230 = (0)(5) + 1/2a(5)

^{2}230 = 0 + 1/2(25)a

460 = 25a

18.4 = a

So, acceleration is 18.4 ft/s

^{2}.Now, using a = 18.4, we'll plug in v

_{i}= 0 and t = 7 and solve for d:d = (0)(7) + 1/2(18.4)(7)

^{2}d = 0 + (9.2)(49)

d = 450.8

So, the stone will have fallen 450.8 feet, which rounds up to 451 feet.