What is the correct way to calculate unit vectors for given vector components?

In summary, the problem does not require any calculation as the unit vector components are already given in the problem and simply need to be written in the correct notation.
  • #1
H2Owned
11
0

Homework Statement


http://img22.imageshack.us/img22/1254/10031833.jpg


Homework Equations





The Attempt at a Solution


My attempt was based on the idea that both triangles formed by the vector components (x component, y component, and the hypotenuse which is the magnitude of the vector itself) would be similar.

I took the length of each of the sides, -3.20 for x and 2.10 for y and individually solved for the unit vector by setting up this relationship:
(length of component)/(length of hypotenuse)=(length unit component)/1

The system rejected both of my answers. For x i got -0.836 and for y i got 0.549.
 
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  • #2
H2Owned said:

Homework Statement


http://img22.imageshack.us/img22/1254/10031833.jpg


Homework Equations





The Attempt at a Solution


My attempt was based on the idea that both triangles formed by the vector components (x component, y component, and the hypotenuse which is the magnitude of the vector itself) would be similar.

I took the length of each of the sides, -3.20 for x and 2.10 for y and individually solved for the unit vector by setting up this relationship:
(length of component)/(length of hypotenuse)=(length unit component)/1

The system rejected both of my answers. For x i got -0.836 and for y i got 0.549.

Your answer looks fine to me. I calculated the same value for the two components. I like that similar triangle method to find unit vectors. In vector classes, you usually just think about it this way(which involves the exact same math): you have a vector A with magnitude A at angle C. You want the same direction(the same angle C) at a magnitude of 1, so you divide by A(the hypotenuse). So yeah, it's the same calculation: each component divided by the hypotenuse.
 
Last edited by a moderator:
  • #3
Maybe it has to do something with unit vector notation. is there a specific notation?Or maybe we both got the answer wrong. Either way I am not getting my homework credit right now
 
  • #4
please help me figure this out, or at least give me your opinions.
 
  • #5
What are you calculating here? Are not the components given in the problem?
The x component is -3.20 and the y component is +2.10, according to the problem. Am I missing something here?
 
  • #6
nasu said:
What are you calculating here? Are not the components given in the problem?
The x component is -3.20 and the y component is +2.10, according to the problem. Am I missing something here?

it turns out that there isn't any calculation necessary, and your answer is correct. i thought the question was asking for a unit vector with the same angle as the given vector.
A Unit vector is a vector with a magnitude of 1, that's where all of my calculations came from - which apparently were unnecessary.
 

What are unit vectors?

Unit vectors are vectors that have a magnitude of 1 and are used to represent direction and orientation.

How do you calculate unit vectors?

To calculate a unit vector, you divide a given vector by its magnitude. The resulting vector will have the same direction as the original vector, but a magnitude of 1.

Why are unit vectors important?

Unit vectors are important because they allow us to easily represent direction and orientation in mathematical and scientific calculations. They also help simplify complex equations by reducing the number of variables involved.

What is the difference between a unit vector and a standard vector?

The main difference between a unit vector and a standard vector is their magnitude. Unit vectors have a magnitude of 1, while standard vectors can have any magnitude. Unit vectors are also used to represent direction and orientation, while standard vectors represent both magnitude and direction.

Can unit vectors be negative?

No, unit vectors cannot be negative. As they have a magnitude of 1, they are always positive values. However, they can point in the opposite direction of a negative vector.

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