Moment vector expression to magnitude of moment

AI Thread Summary
The discussion focuses on finding the magnitude and angle of a moment vector given as moment = -2.8i - 1.53j + 2.24k. Participants clarify that the magnitude of a vector can be calculated by squaring each component, summing them, and taking the square root. There is confusion regarding the use of trigonometric functions to determine angles, with one participant noting that the inverse tangent of the vectors does not yield accurate results. The conversation emphasizes the importance of correctly applying vector magnitude formulas. Overall, the thread highlights common challenges in vector calculations and the need for clarity in solving such problems.
kleeds
Messages
4
Reaction score
0

Homework Statement


find the magnitude and angle of the moment

moment=-2.8i-1.53j+2.24k

force tension=2.4 kN

Homework Equations


rxf=rfsin(theta)

The Attempt at a Solution


i used the cross product to get i j and k
tried sin and cos of vectors but didnt work.
inverse tan of vectors won't give close to correct angles
 
Last edited:
Physics news on Phys.org
Welcome to PF!

As far I as I can tell, the first part of the question is simply asking what the magnitude of the given vector is. You have all three components of the vector.

What is the expression for the magnitude of a vector in terms of its components?
 
I have no idea. The last time i did vectors at least six months ago.
 
nevermind you square them all, add them, then take the square root.
 
kleeds said:
nevermind you square them all, add them, then take the square root.

Yeah.
 
Thread 'Voltmeter readings for this circuit with switches'

Thread 'Voltmeter readings for this circuit with switches'

TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
View full post »
Thread 'Correct statement about a reservoir with an outlet pipe'

Thread 'Correct statement about a reservoir with an outlet pipe'

The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
View full post »

Similar threads

Torque on a Circular Current Loop under a Misaligned Magnetic Field
Replies
1
Views
1K
How to Calculate Moment of a Couple Using Cross Products?
Replies
4
Views
2K
Why is a current ring approx a magnetic dipole from very far off?
Replies
7
Views
2K
Are the 2nd and 3rd problems in this video correctly solved? (charged dipole and organ pipe problems)
Replies
3
Views
1K
Equilibrium of Rigid Bodies. Rafter. What is moment arm?
Replies
1
Views
3K
Magnetic moment and magnetic field and dot product
Replies
13
Views
2K
Rope between inclines with maximum length of hanging middle portion
Replies
46
Views
3K
Calculate electric force using Coulomb's law (vector components are the struggle)
Replies
3
Views
1K
Finding the magnitude of the moment on a pipe wrench
Replies
21
Views
7K
Express the moment (torque) as a function of theta
Replies
9
Views
4K

Hot Threads

Recent Insights

Back
Top