Box being pushed up an inclined plane

Click For Summary

Homework Help Overview

The problem involves a box being pushed up an inclined plane with a specified force and angle. The goal is to determine the normal force and the coefficient of kinetic friction while the box moves at a constant speed.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the resolution of forces acting on the box, particularly the normal force and its direction relative to the inclined plane. There are questions about the calculations of weight components and the implications of multiple-choice answers on the problem-solving process.

Discussion Status

Some participants have provided insights into the relationship between the normal force and the weight components, while others express confusion regarding their calculations and the available answer choices. The discussion reflects a mix of interpretations and attempts to clarify the setup of the problem.

Contextual Notes

Participants are working within the constraints of a multiple-choice format, which may influence their calculations and reasoning. There is also a focus on ensuring that all forces are resolved correctly in relation to the inclined plane.

bajangal1
Messages
5
Reaction score
0

Homework Statement



A 250N force is directed horizontally to push a 29kg box up a plane that is inclined at 27 degrees to the horizontal. the box moves up the plane at a constant speed. Determine the magnitude of the normal force, and the coefficient of kinetic friction.
g=9.8m/s^2
a(y) = 0m/s

Homework Equations


F=mg to find the force that is pulling down on it
Fk= [itex]\mu[/itex] k Fn


The Attempt at a Solution



I understand that the forces need to be resolved into the same direction, but I'm not sure what direction the normal force would be pointing in. The force of gravity i got was 284.2N. I can't figure out the kinetic friction until i figure out the normal force.
 
Physics news on Phys.org
The normal force will be at 90 degrees to the inclined surface, and equal and opposite to the component of the weight of the box acting perpendicularly through the plane.
 
maybe I'm resolving my vectors wrong. when i resolve the vector for weight, the part that should be equal and opposite to Fn I'm getting 129.02N which is not possible as it is multiple choice and that's not even one of the answers
 
What are the options you are given?
 
a) 330N 0.31
b) 310N 0.33
c) 250N 0.27
d) 290N 0.30
e) 370N 0.26

The answer is e
 
To find the components of the weight, draw an angle formed by the vector of weight and a line perpendicular to and under the surface. This angle is equal to the angle of inclination of the plane.
Make the x-axis parallel to the surface, so the y-axis would be perpendicular to the surface and parallel to the normal force.
 

Similar threads

Replies
2
Views
879
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
19
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
46
Views
7K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 27 ·
Replies
27
Views
5K
Replies
3
Views
2K