a boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,ha boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,h m,above the cliff top is given by h=20t-5t^(b)calcu
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a boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,ha boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,h m,above the cliff top is given by h=20t-5t^(b)calcu
a boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,h
a boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,h m,above the cliff top is given by h=20t-5t^
(b)calculate the time which elapses before the stone hits the beach
(c)calculate the speed with which the stone hits the beach
a boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,ha boy stands on the edge of a cliff of height 60m.he throwws a stone upward so that its distance ,h m,above the cliff top is given by h=20t-5t^(b)calcu
(1)20t-5t^2=-60,t=6 seconds
(2)based on the equation of mechanic energy,
the velocity v0=20m/s,so
m*g*h=0.5*m*(vt^2-v0^2)
that is
10*60=0.5*(vt^2-20^2)
vt=40meters per second
time is 6 s