Posted by Kim-lee on .
it is a projectile motion question i just can't seem to figure out
A ball is shot from the ground into the air. At a height of 9.1 m, its velocity is observed to be v = 7.6i + 6.1j m/s
To what maximum height does the ball reach?
the answer is suppose to be 11m
wow...Phys...this has me COMPLETELY clueless -
The vector velocity component that goes with the "j" unit vector is the vertical component. At 9.1 m height, the ball will rise until the vertical component becomes zero. That additional height H can be obtained from energy considerations:
g H = (1/2)(6.1 m/s)^2
which tells you that
H = 1.9 m
Add that to 9.1 m for the answer.