A girl at the bottom of a 100m high cliff throws a tennis ba

Solution:
Define t1 as the time at which two balls meet each other,the distance the tennis has fallen when two balls meet as S1,the distance the golf ball rises as S2,the initail velocity of tennis ball as v0
since the point two balls meet are the top point of golf ball 's path
so that t1=v0/g
then
S1=1/2*g*t1^2
S2= v0*t1-1/2*g*t1^2
get s1=s2=50m
assume g=10m/s^2
t1=10^0.5 s which is about 3.162s
v0=g*t1=31.6m/s
Answer:Q1 With the speed of 31.6m/s the tennis ball is thrown so that the golf ball strikes it at the top of its path
Q2:The meet at the middle point of the cliff which is 50m from both the top and the bottom.
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