Uniform Acceleration Homework: Calculate Distance and Force

[FalconKICK]

Homework Statement

After uniformly accelerating his arm for 0.0500 s, a pitcher releases a baseball of weight 1.40 N with a velocity of 37.0 m/s horizontally forward. The ball starts from rest. (Assume that horizontally forward and upward are positive.)

Homework Equations

a)Through what distance does the ball accelerate before its release?

b)What force does the pitcher

The Attempt at a Solution

I got part of part b What force does the pitcher ___Ni + 1.4Nj

I really just need the equation to find part a.

 

[CompuChip]

Does
v = a t[/itex]<br /> ring a bell? Can you apply that here? <br /> <br /> Also, the phrases &quot;... with a velocity of 37.0 m/s horizontally forward.&quot; and &quot;The ball starts from rest. &quot; sound a bit contradictory to me (I assume they mean: it starts from rest, <i>then</i> the pitcher accelerates it, and when he let&#039;s go, it has a(n instantaneous) velocity of 37.0 m/s).

 

[FalconKICK]

Does
v = a t[/itex]<br /> ring a bell? Can you apply that here? <br /> <br /> Also, the phrases &quot;... with a velocity of 37.0 m/s horizontally forward.&quot; and &quot;The ball starts from rest. &quot; sound a bit contradictory to me (I assume they mean: it starts from rest, <i>then</i> the pitcher accelerates it, and when he let&#039;s go, it has a(n instantaneous) velocity of 37.0 m/s).

<br /> <br /> I tried that but when I input the answer into the site it says it&#039;s wrong.

 

[Doc Al]

What did you try? You need to find the distance it traveled during its acceleration. Start by finding the average speed.

 

[t-money]

I think what compuchip gave you was the final velocity, after the release. From there you can find the acceleration, having the duration (time) of acceleration. then relating that final result to the change in position in the x direction using your kinematic equations to represent mathematically what is going on physically. Having just the equation never really helped me understand how to use them or when to use them.

 

[FalconKICK]

Ok I understood what you guys said and got part a but I'm still sort of confused about part b, the first part of it.

 

[Doc Al]

Apply Newton's 2nd law.