SOLUTION: If an object is dropped from a height of h meters, the velocity v (in m/sec) at impact is given by v= the square root of 2gh , where g= 9.8 m/sec^2 is the acceleration due to gravi

Algebra ->  Conversion and Units of Measurement -> SOLUTION: If an object is dropped from a height of h meters, the velocity v (in m/sec) at impact is given by v= the square root of 2gh , where g= 9.8 m/sec^2 is the acceleration due to gravi      Log On


   



Question 1066144: If an object is dropped from a height of h meters, the velocity v (in m/sec) at impact is given by v= the square root of 2gh , where g= 9.8 m/sec^2 is the acceleration due to gravity.
a. Determine the impact velocity for an object dropped from a height of 40m.
I Know the answer to this is 28 m/sec.
b. Determine the height required for an object to have an impact velocity of 18.8 m/sec (=42 mph). Round to the nearest tenth of a meter.
Cannot figure part b out.. Help???

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
If an object is dropped from a height of h meters, the velocity v (in m/sec) at impact is given by v= the square root of 2gh ,
where g= 9.8 m/sec^2 is the acceleration due to gravity.
a. Determine the impact velocity for an object dropped from a height of 40m.
I Know the answer to this is 28 m/sec.
b. Determine the height required for an object to have an impact velocity of 18.8 m/sec (=42 mph). Round to the nearest tenth of a meter.
Cannot figure part b out.. Help???
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Part b):  sqrt%282gh%29 = 18.8,   or   sqrt%282%2A9.8%2Ah%29 = 18.8.


Solve for h.