March 12th, 2010 | portal.cgkz.com | edit
a rock is thrown horizontally out from the top of a 147m cliff. It hits the ground 80m from the base of the cliff. Would the Delta Y (displacement) be negative 147? Also will g= -9.8?It all depends on what direction you assume as positive to begin. If you assme that up is positive then Delta Y = -147m , but if you assume down to be positive then Delta Y = +147m.
The same applies with gravity.
Which ever direction you chose as positive though, it is important to keep in consistant through out.
So if Delta Y = -147m ( Up is positive), then g= -9.8
If Delta Y = 147m (Down is positive), then g= +9.8#If you have any other info about this subject , Please add it free.# |
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