SOLUTION: When a rock is dropped from a cliff into an ocean, it travels approximately 16t 2 feet in t seconds. If the splash is heard 2 seconds later and the speed of sound is 1100 ft/sec, a

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: When a rock is dropped from a cliff into an ocean, it travels approximately 16t 2 feet in t seconds. If the splash is heard 2 seconds later and the speed of sound is 1100 ft/sec, a      Log On

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Question 494341: When a rock is dropped from a cliff into an ocean, it travels approximately 16t 2 feet in t seconds. If the splash is heard 2 seconds later and the speed of sound is 1100 ft/sec, approximate the height of the cliff. (Give the answer to two decimal places.)

Answer by chessace(471) About Me  (Show Source):
You can put this solution on YOUR website!
Drop for t sec from height x ft.
x = 16 t^2
x = 1100 * (2-t)
16 t^2 + 1100 t - 2200 = 0
t = (-1100 + sqrt(1100^2 - 4*16*(-2200)))/(2*16)
=(-1100 + sqrt(1210000+140800))/32
=(-1100 + 1162.24)/32
=62.24/32 = 1.945 sec
Sound travels for 0.055 sec,
x = 60.5 ft