- #1

Krookwood

- 5

- 0

## Homework Statement

a gold ball is hit with an initial velocity of 52m/s at an angle of 50 degrees

How long is it in the air

## Homework Equations

Sin=opp/hyp

Cos=adj/hyp

D=vt+1/2at^2

## The Attempt at a Solution

First I split the vector into its vertical and horizontal components

sin50=x/52

52sin50=x

x=39.83m/s (up)

cos50=x/52

52cos50=x

x=33.4m/s (Horizontal)

Then I use the kinematic equation to find the amount of time it is in the air considering its total vertical displacement will be 0

d

_{v}=v

_{1}*t+1/2a*t

^{2}

0=(39.83m/s)(t) + 1/2 (-9.8m/s

^{2})t

^{2}

i then factor out "t" and this is where I'm having an issue. I get my equation to look like this

0=t(39.83m/s - 4.9m/s

^{2}t)

and the supposed answer is "0 or 8.1" however I'm unable to get this same result, I may be forgetting something so if anyone could explain how I get this number I'd greatly appreciate it.

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