In an experiment, two identical rocks are simultaneously thrown from the edge of a cliff a distance h0 above the ground. Rock A is thrown vertically upward with speed v0 and rock B is thrown vertically downward with speed v0v0. Rock A and rock B strike the ground at times tA and tB, respectively. Consider the positive vertical direction to be upward.

(a) On the axes given below, sketch and label graphs of the velocity as a function of time for rock A and rock B. Label the time tB. Times tA and 1/2tA are given on the graph.

b) Rock B hits the ground at times tB. Derive an equation for the time tAtA it takes rock A to hit the ground in terms of v0, tB, and physical constants, as appropriate

Velocity r -TT +-H+- III I t -+-1 II I I! T1 T-1 -+ Time 2 A L-I_L_L_L_L. III II 1 +-+TT L-L L -LL L