# Projectile Question (1 Viewer)

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#### SS2006

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#### Jameson

Separate the velocity vector into its two components.

$${V_{x0}}={V_0}\cos{\theta}}$$
$${V_{y0}}={V_0}\sin{\theta}}$$

You can then solve for the total time it will take to hit the ground by working with the y-component, and thus use the x-component to solve for the x displacement.

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#### SS2006

lets say i want to to the v(x)
id get
v(x) = 5 cos ?
i dont know the degree, usually i have 5 cos 60 degrees, then id have a V(x), this time id ont

#### Päällikkö

Homework Helper
As it's fired horizontally, what's the angle?

#### Jameson

Use one of your kinematic equations.... how about $$V_{yf}^2=V_{y0}^2+2gd$$. All of those variables, and gravity, are given to you. What can you solve for now?

#### SS2006

Päällikkö said:
As it's fired horizontally, what's the angle?
180 degrees right, tried that and i got real close, just a 0.01 away, think i got it
thx

#### SS2006

can i use 180 degrees?

#### Päällikkö

Homework Helper
I'd use 0 degrees. With 180 you have to hassle with directions (you get negative cosine).

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