Solve this problem - I was really unclear about how to derive the answer so plea
ID: 2125960 • Letter: S
Question
Solve this problem - I was really unclear about how to derive the answer so please show as much work as possible.
At the edge of a 12-m-tall building, two children throw rocks at 10m/s , one upward and one downward. Find the time until the rock, thrown upward, hits the ground. Express your answer to two significant figures and include the appropriate units. Find the time until the rock, thrown downward, hits the ground. Express your answer to two significant figures and include the appropriate units. Find the speed of the rock, thrown upward, when it hits. Express your answer to two significant figures and include the appropriate units.Explanation / Answer
a.) T = t1 + t2
t1 = 2*u/g = 2*10/9.81 = 1.962sec
t2,
v^2 = u^2 + 2as = 10^2 + 2*9.81*12 => v = 18.31m/s
v = u + at2
t2 = .85sec
T = 2.81 sec
b.) T = t2
it would be same as time y2 that have been calculated before because the case for t2 and this ball is the same
T = .85 sec
c.) in a.) part the velocity has been calculated
v = 18.31m/s