Finding distance traveled up a ramp

Click For Summary

Homework Help Overview

The discussion revolves around calculating the distance traveled up a ramp, involving forces acting on an object on an incline. The subject area includes dynamics and kinematics, particularly focusing on the components of gravitational force and their effects on motion.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants explore various attempts to calculate distance using different equations and approaches, including kinematic equations and force analysis. There are questions regarding the correctness of the weight components and their application in the calculations.

Discussion Status

Some participants provide feedback on the calculations, particularly regarding the components of weight and their roles in determining forces. There is an ongoing exploration of how to incorporate both x and y direction information into the distance calculation, with some participants expressing confusion about the correct approach.

Contextual Notes

Participants note discrepancies in the calculated values for weight components, questioning their validity in relation to the total weight. There is mention of previous calculations affecting current assumptions, and a need to clarify the role of friction in the overall analysis.

x2017
Messages
84
Reaction score
1

Homework Statement


Untitled.png


Homework Equations


ΣFΔt=mΔv
ΣF=ma
v=d/t

The Attempt at a Solution


I already found the following for previous questions:
mg=-661.9
mgx=-3594.37
mgy=-649.91
Fx=2192.69
Fy=-1250.69
FF=-365.44
Vf=257.18
ΣFx=-1767.12

ATTEMPT #1
v=d/t
d=vt
d=(257.18)(10)
d=2571.80 (incorrect)

ATTEMPT #2
ΣFΔt=mΔv
ΣFΔt=m(d/t)
[ΣFΔt/m](t)=d
[(-1767.12)(10)/67.4]10=d
-2621.84=d

ATTEMPT #3
ΔV=Δd/Δt
ΔvΔt=Δd
(257.18-5)(10)=Δd
2521.80=Δd

I am not sure where I am going wrong!
 
Last edited:
Physics news on Phys.org
Your x and y components of the weight are greater than the weight.
 
TSny said:
Your x and y components of the weight are greater than the weight.
IMG_0105.JPG


I keep getting the same things (Sorry about the bad quality photo, but I figured this was best so the triangles I made can be seen).
 
In your pink triangle drawn on the inclined plane, note that mg is the hypotenuse. But in the work shown in the blue rectangle you have mgx as the hypotenuse.
 
TSny said:
In your pink triangle drawn on the inclined plane, note that mg is the hypotenuse. But in the work shown in the blue rectangle you have mgx as the hypotenuse.

If I use the pink triangle again for mgx and use cos I get mgx=121.63.
But I'm confused because I still got 3594.37 for mgy & that's much larger than mg (661.19) in the first place, so is that one incorrect?

EDIT: mgy has to be correct because I had to calculate the force of friction in a previous question with it and obtained the correct answer!
 
x2017 said:
But I'm confused because I still got 3594.37 for mgy & that's much larger than mg (661.19) in the first place, so is that one incorrect?

EDIT: mgy has to be correct because I had to calculate the force of friction in a previous question with it and obtained the correct answer!
In the pink box you got the correct value for mgy.

Your value for mgx now looks correct also.
 
TSny said:
In the pink box you got the correct value for mgy.

Your value for mgx now looks correct also.

Okay, thanks!

So am I supposed to use both when solving for distance or just the stuff in the x direction? I was only using the stuff in the x direction before.
 
You need to use the y direction information to help get the friction force. But once you have the friction, you just need to consider ΣFx = max.
 
TSny said:
You need to use the y direction information to help get the friction force. But once you have the friction, you just need to consider ΣFx = max.

Okay so:

ΣFx=max
Fx-FF-mgx=max
2192.69-365.44-121.63=67.4[(vf-vi)/Δt]
(1705.62/67.4)10=vf-vi
253.06=Δv

And this is where I get lost... I am stuck solving for a distance, I don't know how to proceed.
 
  • #10
Never mind, I figured it out!

d=[(vi+vf)/2]t
d=[(5+257.18)/2]10
d=1310.90m
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 19 ·
Replies
19
Views
2K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
3
Views
2K
Replies
4
Views
16K
Replies
2
Views
4K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
3
Views
3K
  • · Replies 13 ·
Replies
13
Views
4K