There are no horizontal forces.
Therefore there is NO change in horizontal velocity !!!
During Service, a tennis ball is struck at height, h = 1.95 m, above a tennis court and moves with velocity Vo= Voxi. Assume the ball encounters no air resistance, and use a Cartesian coordinate system with the origin located at the balls initial position. Vox = 24.5 m/s
a) Calculate the tennis balls horizontal velocity, Vfx in m/s, when it strikes the court.
b) How long, tf, in seconds does the tennis ball move before striking the court?
c) How far horizontally from the service position, xf, in meters does the tennis ball move before striking the court?
Please show me what formulas you will use to solve this because I don't even know how to start calculating it.
Thanks!!
5 answers
Now the vertical problem is another matter entirely.
The ball has no initial speed up or down
F = - m g is the vertical force
therefore
m a = - m g
a = -g constant acceleration down of about 9.81 m/s^2
The ball has no initial speed up or down
F = - m g is the vertical force
therefore
m a = - m g
a = -g constant acceleration down of about 9.81 m/s^2
then
v = 0 - a t = - g t = -9.81 t
h = Hi + 0 t -9.81/2 t^2
h = 1.95 - 4.9 t^2
ground is h = 0
so when it hits the floor
t^2 = 1.95.4.9
solve for t
Now for t seconds, the horizontal velocity was constant = 24.5 m/s
x = v t = 24.5 t
v = 0 - a t = - g t = -9.81 t
h = Hi + 0 t -9.81/2 t^2
h = 1.95 - 4.9 t^2
ground is h = 0
so when it hits the floor
t^2 = 1.95.4.9
solve for t
Now for t seconds, the horizontal velocity was constant = 24.5 m/s
x = v t = 24.5 t
Thank You !!!! I got it correct!
atta go :)
1 answer