# Homework Help: Vector Size

1. Sep 22, 2010

### huybinhs

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

Five vectors are listed below. Select them in order of increasing magnitudes, from shortest to longest. If B is smallest, then A, C, D, and finally E is the largest, enter BACDE (Note: If of equal length, then enter in the order listed.)
A) 23i-31j-17k
B) 36j+26k
C) 43j
D) 20i-34j-20k
E) 30i+30j

2. Relevant equations

magnitude = sqrt (i^2 + j^2 + k^2)

3. The attempt at a solution

I found:

A = 42.178

B= 44.407

C = 43

D = 44.226

E 42.426

I ranked: AECDB or even follow the order list: AECBD => It's showing wrong???

Could anyone explain what's going on? I'm really confused because I think I'm doing the right way!!!

Thanks!

2. Sep 22, 2010

### Thaakisfox

As i see you squared the coordinates and took the root of their sum. Well thats the right way. probably some computation error. but the method is correct.

3. Sep 22, 2010

### huybinhs

Anyone has different ideas?