# sciecne

posted by .

In unit-vector notation, what is the sum of vector a =(4m)i + (3m)j and vector b= (-13m)i +(7m)j?

a)I got (27m)i +(10m)j but the book said it should have been (-9m)i +(10m)j

b)what is the magnitude and direction of vector a + vector b (relative to i)?

to find the magnitude i did the sqrt((-9^2 + 10^2) and then I got 13.453
I wasn't sure how to find the direction.

I am wondering how you got 27i? The i component of a was 4, and the i component of b was -13. Adding them gets the book answer.

Magnitude of the sum: (-13)^2 + (10)^2= 269, and the square of that is ....

Direction: arctan (10/-13)

jytttttttttttttttttttttttmhg

## Similar Questions

1. ### Physics

The two vectors a and b have equal magnitudes(on an x-y plane vector a is 30 degrees from the x axis then vector b is 75 degrees from the head of vector a it is heading towards north west) of 10m A)find the x component of their vector …
2. ### Physics

Use the definition of scalar product( vector A* vector B = abcos theda and the fact that vector A * vector B = axbx+ ayby+azbz to calculate the angle between the two vectorgiven by vector A= 3i + 3j + 3k and vector B= 2i + 1j + 3k. …
3. ### Physics

The three vectors have magnitude a =3m, b= 4m and c=10m . On the x axis is vector a at 0 degrees then 30 degrees is vector b then 120 degrees is vector c. If vector c =p*vector a + q*vector b .What are the values of p?
4. ### Math - vectors

In the product F(vector)=q(V(vector)xB(vector), take q = 4, V(vector)= 2.0i + 4.0j + 6.0k and F(vector)= 136i -176j + 72k. What then is B(vector) in unit-vector notation if Bx = By?
5. ### Physics

When two vectors vector A and vector B are drawn from a common point, the angle between them is phi. If vector A and vector B have the same magnitude, for which value of phi will their vector sum have the same magnitude as vector A …
6. ### physics

Vector vector A has a magnitude of 6.90 units and makes an angle of 46.5° with the positive x-axis. Vector vector B also has a magnitude of 8.00 units and is directed along the negative x-axis. Using graphical methods find the following. …
7. ### Physics

Let vector A = 4i^ + 4j^, vector B = -2i^ - 5j^, and vector F = vector A - 5(vector B). a) Write vector F in component form. vector F = ?
8. ### Physics

Let vector A = 4i^ + 4j^, vector B = -2i^ - 5j^, and vector F = vector A - 5(vector B). a) Write vector F in component form. vector F = ?
9. ### calculus

State whether or not the following statements are true. Justify your reasoning.?
10. ### Physics

Part A of this question asks for the sum of vector A = 3x+5y and vector B = 1x-3y. I did this and got the vector A + vector B = 4x+2y. Part B then asks what the magnitude and direction of vector A + vector B?

More Similar Questions