Need help with projectiles initial velocity using height and distance

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The discussion revolves around calculating the initial velocity of a projectile, specifically a baseball, that traveled 180 meters and reached a height of 21.3 meters. The user applies the equation u^2 = v^2 - 2as, where they set v to 0, s to 180, and a to -9.8 m/s², leading to an initial velocity of approximately 59.9 m/s. Questions arise regarding the correct use of the equation, the need to find the angle of projection, and the definitions of variables such as u, v, and s. Additionally, there is confusion about the role of gravity in horizontal motion and whether it affects vertical acceleration. Clarifying these concepts is essential for accurately solving the projectile motion problem.
batcave1985
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home run that was estimated to have
landed 180 metres from the home plate and to have reached a
height of 21.3 metres. Calculate the initial velocity of the
ball.

u^2=v^2-2as

t=?
u=?
v=0
s=180
a=g= -9.8

u^2= √0^2-2x-9.8x180
u= 59.9 m/s


am I using the right equation for this problem. I am not sure if I have to find the angle using the height and the range of the ball to help find the initial velocity. just want to know if this is the right direction with this problem
 
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What are u and v? What is s? And why do you not use the maximum height? Does the ball move horizontally? If so, is g the horizontal acceleration? Does not accelerate Earth the objects vertically?

ehild
 

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