What is the speed of the ball the moment before it strikes the ground (in m/s)?
(projectile motion problem)
I don't know the angle... so I don't know what to do :(
(projectile motion problem)
I don't know the angle... so I don't know what to do :(
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You don't need the angle.
Find the vertical speed component (v) on hitting the ground.
v² = u² +2as (or vf² = vi² + 2as if you use those symbols)
In a vertical direction, initial vertical velocity component, u =0. Taking up as positive:
v² = 0² +2(-9.8)(-1.5)
v = √29.4 = 5.42m/s
To get the total speed, add the vertical and horizontal components using vector addition (Pythagoras):
V = √(5.42² + 7.8²) = 9.5m/s
There 's a very similar calculation in the link at about 8mins 18 seconds.
Find the vertical speed component (v) on hitting the ground.
v² = u² +2as (or vf² = vi² + 2as if you use those symbols)
In a vertical direction, initial vertical velocity component, u =0. Taking up as positive:
v² = 0² +2(-9.8)(-1.5)
v = √29.4 = 5.42m/s
To get the total speed, add the vertical and horizontal components using vector addition (Pythagoras):
V = √(5.42² + 7.8²) = 9.5m/s
There 's a very similar calculation in the link at about 8mins 18 seconds.