What is the velocity, speed, position and distance traveled after 30 minutes?

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Homework Help Overview

The discussion revolves around a physics problem involving a boat (later clarified as a hot air balloon) moving with an initial speed and constant acceleration in three-dimensional space. Participants are tasked with determining the velocity, speed, position, and distance traveled after a specified time interval of 30 minutes.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Problem interpretation, Assumption checking

Approaches and Questions Raised

  • Participants explore the application of kinematic equations in three dimensions, questioning how to separate the motion into components. There is discussion about the implications of the acceleration vector and how it affects velocity and distance calculations.

Discussion Status

Several participants have provided guidance on breaking down the problem into components and applying kinematic equations. There is an ongoing exploration of the correct approach to find the final position and distance traveled in each direction, with no explicit consensus reached on the final answers.

Contextual Notes

Participants express confusion regarding the nature of the problem, particularly the implications of the given acceleration and the physical feasibility of the scenario. There are mentions of needing to define starting coordinates and the significance of initial conditions in the calculations.

  • #31
physics(L)10 said:
I understand that (z=up, y=toward you, x=across) I just don't understand how to apply it to the equations and which equations to use.

Well let's apply that to the situation. Forget the equations for the moment, and just think about what's going on.

You said it's a balloon,
so it can move north/south. We'll call that X.
With south in the +ve direction.

East/west we'll call that Y.
East in the +ve direction.

Up/down we'll call that Z.
Up is +ve.So the balloon can move in 3 different axis. In reality it can move in any direction. But that real movement can be defined as though you walked up/down, east/west, north/south.Do you know what resultants and components of something are?edit: I'm leaving work now. if you don't know what they are read the following:
http://hyperphysics.phy-astr.gsu.edu/hbase/vect.html
http://www.mathwarehouse.com/vectors/resultant-vector.php
 
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  • #32
Isn't Up and down the same thing as north and south?

resultant is formed when you add/subtract two vectors together. components I probably know but I don't know they're called components so I don't know lol.

edit: component is a particular vector ex. (-1,10)?
 
Last edited:
  • #33
I've been working on it and I think I mightve gotten something:

r=(0,0,0)
u=(0,0,0)
a=(10,5,10)

and then you use the equation x=Xo +ut + at^2/2 for x,y,z and you get 3 velocity values. Now I'm stumped
 
  • #34
physics(L)10 said:
Isn't Up and down the same thing as north and south?

Up and down is elevation.

physics(L)10 said:
resultant is formed when you add/subtract two vectors together. components I probably know but I don't know they're called components so I don't know lol.

and then you use the equation x=Xo +ut + at^2/2 for x,y,z and you get 3 velocity values. Now I'm stumped

Yep you should have 3 velocity values, and three displacement values.

Look at this graph. There are three pink lines, one going down x, along y and then up z. Those three that you've calculated correspond to those lines. Also you can see that the three displacements give you the new position (x,y,z).

What you now want to do is find the resultant of those three vectors. So that the path taken takes you straight from (0,0,0) to (x,y,z). #This is what you found originally.
 
  • #35
physics(L)10 said:
I've been working on it and I think I mightve gotten something:

r=(0,0,0)
u=(0,0,0)
a=(10,5,10)

and then you use the equation x=Xo +ut + at^2/2 for x,y,z and you get 3 velocity values. Now I'm stumped
What do the equations that you have written down represent? If you want to write the three vectors at time t = 0, you should write

r=(0,0,0)
u=(10,0,0)
a=(10,5,10)

Note that the x component of the initial velocity is 10 m/s as given by the problem. Now can you write the position, velocity and acceleration vectors not at just t = 0 but at any time t? Hint: The acceleration vector will be the same. What about the other two?
 
  • #36
Alright, thanks guys I think I got it.
 

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