# Vectors and component vectors

## Homework Statement

Vector A lies in the yz plane 65.0° from the positive direction of the y axis, has a positive z component, and has magnitude 5.10 m. Vector B lies in the xz plane 42.0° from the positive direction of the x axis, has a positive z component, and has magnitude 1.70 m. Find (a) A*B, (b) the x-component of AxB, (c) the y-component of AxB, (d) thez-component of AxB, and (e) the angle between A and B[/B]

The attempt at a solution

I tried using typical procedure of getting the dot and the cross product the problem is I don't know what to put in Vector A I tried 5.10cos65 but it was wrong so any help will be great thankyou!

Orodruin
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the problem is I don't know what to put in Vector A I tried 5.10cos65
It is unclear what you mean by "what to put in Vector A". It is a vector and cannot be described with a single number. Please show all your work and what you are trying to do.

It is unclear what you mean by "what to put in Vector A". It is a vector and cannot be described with a single number. Please show all your work and what you are trying to do.

Okay sorry. What I mean is I don't know how to get Vector A and Vector B. Is there something I need to do for to know this or what?
I only kmow how to dot product and cross product if it is an ijk (just get the magnitude and etc) the problem in this question is the given is an given angle and a magnitude so I tried getting 5.1cos65 to get the x component which is I assume the same as i hat?
I don't know if my logic is right so any help will be appreciate thankyou!

Ali.B.
Α=( 0 , 5.10cos65 , 5.10sin65 )
B=( 1.70cos42 , 0 , 1.70sin42)
Now they are in ijk ( as you say) so you can dot or cross them, dude!

It is unclear what you mean by "what to put in Vector A". It is a vector and cannot be described with a single number. Please show all your work and what you are trying to do.
Α=( 0 , 5.10cos65 , 5.10sin65 )
B=( 1.70cos42 , 0 , 1.70sin42)
Now they are in ijk ( as you say) so you can dot or cross them, dude!

There's a 0 because it is stated in the first given that it is only on the yz plane?
So I just get the magnitude of it then continue with the dot and cross product?

EDIT: THANKYOU I GOT THE CORRECT ANSWER.
My only mistake is I didn't include zeros in my solution thankyou thankyou

Last edited:
Ali.B.
Youre welcome, hiineko!
Are u a physics student?

Youre welcome, hiineko!
Are u a physics student?

Yes I am. Under my mechanical engineering curriculum.