Register to reply

Force projection onto body's axis

by Bismuth
Tags: axis, body, force, projection
Share this thread:
Sep20-10, 12:09 AM
P: 6
Hey PhysicsForums. Long time reader looking for some assistance

1. The problem statement, all variables and given/known data

2. The attempt at a solution

I'm pretty sure the idea is to find the unit position vector to point A, and the force vector F.

I found the unit position vector to be u = (-4/6)i +(4/6)j + (2/6)k, and the force to be F = (560cos60sin30)i + (560cos60cos30)j + (560sin60)k

Dotting them together gives me 230 lb, but Mastering Engineering doesn't agree with me. Can anyone point out where I went awry?

Thanks for reading!
Phys.Org News Partner Science news on
Final pieces to the circadian clock puzzle found
A spray-on light show on four wheels: Darkside Scientific
How an ancient vertebrate uses familiar tools to build a strange-looking head
Sep20-10, 04:28 AM
Sci Advisor
HW Helper
PF Gold
P: 11,866
The x-component of F should be negative. The rest looks fine to me.
Sep20-10, 08:24 AM
P: 6
Simple mistakes are embarassing :(

Thank you for your careful eyes!

Register to reply

Related Discussions
Finding a Force using the dot product/projection (Calc 3) Calculus & Beyond Homework 2
A circular body motion around its axis General Physics 1
One force represented along an x-axis Introductory Physics Homework 2
Free body diagram involving normal force, gravitational force, and applied force. Introductory Physics Homework 4
Projection with coriolis force Introductory Physics Homework 1