Defenestration homework not going so well -_-

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Homework Help Overview

The discussion revolves around a physics problem involving a ball thrown horizontally from a height of 53.8 m, striking the ground 119 m away from the building. Participants are exploring kinematic equations to determine various components of the ball's motion, including initial velocity and velocity components just before impact.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the horizontal distance traveled by the ball and the time of flight. They question the initial vertical velocity and its implications on the motion. There is exploration of which kinematic equations apply to the problem, particularly in relation to horizontal and vertical components of velocity.

Discussion Status

Some participants have attempted to apply various kinematic equations but express confusion regarding their effectiveness. There is a recognition of the need to clarify the relationship between horizontal and vertical motion, particularly in terms of initial velocities and acceleration. Multiple interpretations of the problem are being explored, with no clear consensus yet.

Contextual Notes

Participants note that the initial y-velocity is unstated, and there is discussion about the effects of acceleration on the different components of motion. The original poster has provided a specific time for the ball's flight but is struggling with subsequent calculations.

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A ball is thrown horizontally from the top of
a building 53.8 m high. The ball strikes the
ground at a point 119 m from the base of the
building.
The acceleration of gravity is 9.8 m/s. The time (I got this answer and it's correct and all) is 3.3135sec.
(part 2 of 4) Find the initial velocity of the ball.
(part 3 of 4) Find the x component of its velocity just before it strikes the ground.
007 (part 4 of 4) 10.0 points
Find the y component of its velocity just before it strikes the ground.vaverage = d/t

a = Vdelta/t

vf = vi + at

I don't even know any others -_-

I tried to use vf^2 = vi^2 + 2ad?? It didn't work. I am really lost but if someone could tell me which formula (kinematics) to use that would be great.I already got the time (part 1 of 4) to equal 3.3135sec but despite using the right equations etc I can't get the other three parts.
 
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The ball was thrown horizontally. How far did it travel horizontally? Over what time? What can change the horizontal velocity?

What's its initial y-velocity? What could change the y-velocity?
 
gneill said:
The ball was thrown horizontally. How far did it travel horizontally? Over what time? What can change the horizontal velocity?

What's its initial y-velocity? What could change the y-velocity?

Accelerationg would change it, and I tried the answer (online homework) in both negative and positive?? The initial y-velocity goes unstated.
 
liagee said:
Accelerationg would change it, and I tried the answer (online homework) in both negative and positive?? The initial y-velocity goes unstated.

Acceleration would change what in particular?

The ball was thrown horizontally. What does that mean for the x and y components of the initial velocity?

What equation describes the x-position with respect to time? How about the y-position?
 
gneill said:
Acceleration would change what in particular?

The ball was thrown horizontally. What does that mean for the x and y components of the initial velocity?

What equation describes the x-position with respect to time? How about the y-position?

Acceleration would change the velocity only in the y-direction. Acceleration and therefore velocity in the x-direction remain constant, with accelerationx=0 m/s.

[itex]\Delta[/itex]s=vit + .5 (a)(t2)

Thanks so much!
 
Actually that didn't work either -___-
 
liagee said:
Actually that didn't work either -___-

Didn't work for what? You'll have to be more specific. There are several parts to the problem. What are you trying to find first?
 
Sorry if I missed it. What's Defenestration?
 
Sorry if I missed it. What's Defenestration?
 

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