A rock dropped from a bridge takes 3.21 seconds to hit the water. How high is the bridge in meters?
I need to find Vsub0 to be able to calculate h....but how do I get Vsub0???
8 answers
is it -9.80 x 3.21= -31.458 is Vsub0??
h=151.47m??
the initial speed is zero. It was dropped, not thrown.
accck ok so
1/2(9.80)(3.21)^2= 50.5 m
1/2(9.80)(3.21)^2= 50.5 m
(1/2)(9.81)(3.21)^2 = 50.5 meters
I'm learning slowly but surely!
more formally
h = Hi + Vi t - 4.9 t^2
0 = Hi + 0 - 4.9 t^2
Hi = 4.9 *3.21^2 = 50.5
h = Hi + Vi t - 4.9 t^2
0 = Hi + 0 - 4.9 t^2
Hi = 4.9 *3.21^2 = 50.5
yes, good
3 answers