Question

whats R?

A 3m south of east
B 3m north
C 3m 30 degrees north east
D 3m 50 degrees south west

Answer 1

what's the general question ? ^_^

Answer 2

whats R? Magnitude of R and direction of R.

Answer 3

how can we determine the magnitude of R and direction of R if there's no problem lol?

Answer 4

i can show you a sample of a previous problem and how it's done.

Answer 5

Nikolas Oman April 17 at 6:46pm
best way to resolve each vector into perpendicular components.
i = positive horizontal direction (to the right)
j = positive vertical direction (up)

A = -5 cos 65 i + 5 sin 65 j

B = 5 cos 50 i - 5 sin 50 j

C = -5 cos 45 i - 5 sin 45 j


R = A + B + C = (-5 cos 65 + 5 cos 50 - 5 cos 45) i + (5 sin 65 - 5 sin 50 - 5 sin 45) j

R = -2.435 i - 2.834 j

Now use the Pythagorean Theorem to get the magnitude:

Magnitude of R = √(2.435² + 2.834²) = 3.7 m

Direction of R = arctan(-2.834/-2.435) = 229.3° ... so that's 49.3° south of west

Answer 6

that's the question? :)

Answer 7

no thats another problem. question is whats the magnitude and direction of R if vectors are:

A 3m south of east
B 3m north
C 3m 30 degrees north east
D 3m 50 degrees south west

Answer 8

LOL >_< my bad, I thought those were the choices ^^"

Answer 9

lol no
do you know how to do it?

Answer 10

I'll give it a try? :)

Answer 11

tnx :)

Answer 12

np ^_^

Answer 13

remind me,

In the previous problem, A = -5 cos 65 i + 5 cos65 j < -- angles were given? or is that the general form

Answer 14

angles were given

Answer 15

how about for this problem?

Answer 16

A 3m south of east
B 3m north
C 3m 30 degrees north east
D 3m 50 degrees south west

Answer 17

this is all that's given

Answer 18

hmm, that means that you have to figure out the angles from the given

Answer 19

B is easy, 3 m north , angle = 90 degrees

Answer 20

hmm yea and A? 45 degrees?

Answer 21

since they haven't given you the angles, yes you can assume that A = 45 degrees

Answer 22

and now? how much is R?

Answer 23

all you've got to do is use the same way you've used in the previous question :)

I think your prob was trying to figure out the angles? right?

Answer 24

well it's not my homework :) it's my friends homework and I have no idea how to do it :)

Answer 25

lol >_<

Answer 26

Alright, let's try to solve it together ^_^

Answer 27

she solved it and got 2.79m 1.65 degrees north of east and she just wants to check if it's ok

Answer 28

so:

i = positive horizontal direction (to the right)
j = positive vertical direction (up)

then we can say the following :

A = 3 cos 45 - 3 sin 45
B = 3 sin 90
C = 3 cos 30 + 3 sin 30
D = - 3 cos 50 - 3 sin 50

Answer 29

yep i agree so far

Answer 30

now:

R = A + B + C
= (3 cos 45 - 3 sin 45 ) + (3 sin 90 ) + (3 cos 30 + 3 sin 30) + (-3 cos 50 - 3 sin 50)
= 0 + 3 + pi - 4.23
= 1.912

Answer 31

R= 3 cos 45 + 3 cos 30 - 3 cos 50)i + (3 sin 45 + 3 sin 90 + 3 sin 30 - 3 sin 50)j

Answer 32

lol, wait, I've messed it up

Answer 33

yeah, hold on :)

Answer 34

ok

Answer 35

R = 1.76 i - 3.32 j

I might have some calculation mistakes, it happens ^_^

Answer 36

so this is it?

Answer 37

\[R = \sqrt((1.76)^2 + (3.32)^2)\]
= 3.74 m

Answer 38

alright thank you so very much!

Answer 39

arctan = -62.07

Answer 40

np :)

Answer 41

thank you thank you
so her answer was wrong?

Answer 42

I'm not sure what was her answer lol , I just followed the steps and given :)

Answer 43

ok thank you!

Answer 44

np ^_^, but I'm not sure though ^^"

Answer 45

is there an online calculator where i could check this?

Answer 46

there's your hand-calculator? :)

Answer 47

i dont have it :/

Answer 48

can you calculate this for me please?
R = (3 cos 45 + 3 cos 30 - 3 cos 50)i + (-3 sin 45 + 3 sin 90 + 3 sin 30 - 3 sin 50)

Answer 49

I did lol, that's what I got, answer above

Answer 50

you can check with your calculator if you want :)

Answer 51

oh ok thank you again :)

Answer 52

lol, np ^_^