Calc 3-Throwing a baseball at 30 degrees from horizontal

riverjib

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Can somebody please help me with the following?

A baseball is thrown from the stands 32ft above the field at 30 degrees from horizontal. When and how far away will it land if the initial speed is 32ft/sec?

Thanks :)
 
Re: Calc 3-Throwing a baseball

\(\displaystyle x=(V_{0}cos(\theta)t\)

\(\displaystyle y=s_{0}+(V_{0}sin(\theta))t-\frac{1}{2}gt^{2}\)

First, we can solve for t by setting y=0 in the last equation and solving for t.

\(\displaystyle 0=32+32sin(30)t-16t^{2}\)

Solve this for t to find the time 'til it hits the ground. Then sub that t value into the formula for x to find how far away it lands,
 
Re: Calc 3-Throwing a baseball

Thanks! Is it really that simple in multivariable terms? Because I did solve it this way since based upon what I knew from Physics, but I thought there was more to it since we're working in three dimensions.
 
Isn't the question working with 2 dimensions? Looks like a projectile motion question to me
 
The ball will remain in the air for a total of

t =[vsin? + ?(v²sin²?+2gh)]/g where v=32, g=32,h=32 and ?=?/6. Hence t = 2 sec.

The ball will go a horizontal distance of

d =[ (v²cos?)/g] [sin?+?(sin²?+2gh/v²)]. Hence d = 32?3 feet.
 
A baseball is thrown from the stands 32ft above the field at 30 degrees from horizontal. When and how far away will it land if the initial speed is 32ft/sec?

Vv = 32sinµ = 16
Vh = 32cosµ 27.7128
1--From Vf = Vo - gt, o = 16 - 32t1 making t1 = .5 sec.
2--From h = Vvt1 - 32t1^2/2, h1 = 16(.5) - 16(.5^2) = 4 ft.
3--From h2 = Vvt2 + 16t2^2, 36 = 0 + 16(t2^2 making t2 = 1.5sec.
4--WIth T = .5 + 1.5 = 2 sec., d = 2(32)cosµ = 55.42 ft.
 
Note: If you have a plethora of problems like this, make up a template or two

(I gave you two equations) and instead of having to do a lot of grunt work, just plug in your

values to the appropriate template, and walla, you have solve the problem without the

usual expenditure of time.
 
Re: Calc 3-Throwing a baseball

riverjib said:
....but I thought there was more to it since we're working in three dimensions.

You have 2-D problem - If the ball was swinging in/out of the strike zone then it would be a 3-D problem.

However, 3-D problems are similar - write those equations in each individual dimensions - and then add those vectorially - simple (tongue firmly planted in the cheek).
 
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