My first week in hs physics and my teacher hasn't taught a thing

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A student is struggling with a physics problem involving a ball thrown upward from a height, needing to calculate its speed upon hitting the sidewalk. They attempted to use the equation for distance but are unsure of the kinematic equations necessary for solving the problem. Another participant suggests looking up kinematic equations for better understanding. The discussion shifts to the student's experience with their teacher, who seems to be challenging them but is ultimately seen as less intimidating as the material becomes easier. The student finds a helpful study book that simplifies the concepts.
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Homework Statement


A boy throws a ball upward at 2.om/s out a window 2.5m above the sidewalk. The ball accelerates at 9.81m/s^2. How fast is it moving when it hits the sidewalk?


Homework Equations


i tried to use the equation: d= initial velocityxtime + .5(acceleration) (Time^2)


The Attempt at a Solution


2.5= 0 + .5(9.81)t^2
2.5=4.9m/s^2 x t^2
2.5/4.9= t^2
?
 
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natabong said:

Homework Statement


A boy throws a ball upward at 2.om/s out a window 2.5m above the sidewalk. The ball accelerates at 9.81m/s^2. How fast is it moving when it hits the sidewalk?


Homework Equations


i tried to use the equation: d= initial velocityxtime + .5(acceleration) (Time^2)


The Attempt at a Solution


2.5= 0 + .5(9.81)t^2
2.5=4.9m/s^2 x t^2
2.5/4.9= t^2
?

Hey there natabong :smile: Can you list for me the other important kinematic equations (or the 'DVAT' Eqs) as they will be of use here.
 
I have no idea what that means. what are kinematic equations?
 
Try googling them or better yet, look in
your text :smile:

It doesn't matter how bad your teacher is;
you will have the biggest impact
on your grade. :wink:
 
yeah, you're definitely right. Actually, i think he was just trying to scare us. It's getting a LOT easier.. right now we're doing vectors and scalars and its a breeze. There's also this study book that i got called "High marks" it's really awesome. It breaks down everything. He told us that the above problem was too hard for high school lol.
 
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