Calculating Moment of Force for 300kg Crate Around Support A | 3000N Force

  • Thread starter Thread starter John78
  • Start date Start date
  • Tags Tags
    Force Moment
Click For Summary

Homework Help Overview

The discussion revolves around calculating the moment of force exerted by a 300 kg crate around a support point labeled A, with a force of 3000 N applied. Participants are examining the relationships between forces and distances in the context of static equilibrium.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants present calculations involving the weight of the crate and the moments around support A. Some express uncertainty about the correctness of their calculations, while others question the assumptions made regarding the crate's dimensions and center of mass.

Discussion Status

There is an ongoing exchange of calculations and interpretations of the problem. Some participants offer checks on the calculations, while others raise concerns about missing information, such as the size of the crate and its center of mass. The discussion reflects a mix of confidence and uncertainty regarding the approach taken.

Contextual Notes

Participants note the lack of information about the dimensions of the crate, which is relevant for determining the center of mass. There is also mention of rounding off values in calculations, indicating a consideration of precision in the results.

John78
Messages
21
Reaction score
0

Homework Statement



Calculate the moment of the force exerted by the crate around support A.

Homework Equations



crate = 300 kg
1 kg=10N
300Kg*10=3000N

The Attempt at a Solution



Ra*42 m = 3000N *6m
Ra = 428,57 N

Rb*42 m = 3000N *36m
Rb=2571,42 N


I just want to check whether my working is correct or not.
 

Attachments

  • 1.JPG
    1.JPG
    3.2 KB · Views: 433
Physics news on Phys.org
It's easy
 
not for every one :C
 
It is not easy because you have not been told the size of the box!
The moment of the box = weight x distance of centre of mass from A
 
I know only that crate = 300 kg
 
My calculation looks like that

crate = 300 kg
1 kg=10N
300Kg*10=3000N

Ra*42 m = 3000N *6m
Ra = 428,57 N

Rb*42 m = 3000N *36m
Rb=2571,42 N

MA=3000N*6m-2571,42
MA=-89999,64

Ra+Rb=428,57+2571,42=2999,99=3000N!

So the answer is Ra = 428,57 N

Am I right i thinking?
 
if you assume that the cm of the crate is at 6 m from the left, your calculations are good, ecept that you should round them off to about 400N and 2600 N, respectively.
 

Similar threads

  • · Replies 14 ·
Replies
14
Views
6K
Replies
6
Views
3K
Replies
4
Views
1K
Replies
17
Views
5K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
1
Views
5K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 24 ·
Replies
24
Views
3K
Replies
2
Views
1K
  • · Replies 5 ·
Replies
5
Views
7K