How to Represent and Convert These Vectors?

[cary1234]

ow I am sorry.haha!

i forgot to tan-1 it..

the answer = 56.31 deg.

:)

for this question

c(->) = 125m/s 75deg north of east

e(->) = 500 kg m/s (hey, what should i do in that kilogram meter/second? thatas what makes me confuse) 18 deg south of east.

s(->) = 707m 26 deg west of south


do u think they are connected to each other sir?


i create a graph of them individual here it is.
please correct me if I am wrong.

http://img509.imageshack.us/img509/251/78228931.png http://g.imageshack.us/img509/78228931.png/1/

 

[tiny-tim]

Hi cary1234 !

(been out all afternoon)

c(->) = 125m/s 75deg north of east

Yes, except that that angle looks nothing like 75º …

75º should be nearly vertical.

And (this goes for all three answers) you should either put an arrow on your vector, or mark which end the origin is.​

e(->) = 500 kg m/s (hey, what should i do in that kilogram meter/second? thatas what makes me confuse) 18 deg south of east.

(kg m/s is a momentum.

Momentum is a vector, just like velocity.

The drawing is exactly the same.)​

No, you've drawn 72º south of east.

Read it … "18 deg south of east" means you start at east, and go 18º south.

s(->) = 707m 26 deg west of south

Yes, the hypotenuse is in the correct direction, but that's a very strange way of drawing it.

You've drawn the triangle as if the question said "64º south of west".

I agree they're the same thing, but it would be more natural to draw the triangle under the hypotenuse, rather than on top of it, so we can see the 26º being south-and-west-y instead of north-and-east-y, as you've drawn it.

do u think they are connected to each other sir?

i can't see any connection.

and don't call me sir! …

i'm only a little goldfish ​

 

[cary1234]

you mean like this?
the truth is i only know how to get the other angles but i don't know where toplace them.
thanks for the information now i know where to place them.
is this correct?

http://img341.imageshack.us/img341/1923/41728774.png http://g.imageshack.us/img341/41728774.png/1/

And (this goes for all three answers) you should either put an arrow on your vector, or mark which end the origin is.

do you mean like this?

http://img215.imageshack.us/img215/9232/43404868.png http://g.imageshack.us/img215/43404868.png/1/

and don't call me sir! …

I'm only a little goldfish

ow youre not a little goldfish. :)
youre a cute little goldfish.. hehe.. :)
or maybe a shark? :)

 

[tiny-tim]

HI cary1234!

(just got up :zzz: …)

you mean like this?
the truth is i only know how to get the other angles but i don't know where toplace them.

That's why those nice professors give you plenty of practice, so that you get used to it before the exam!

thanks for the information now i know where to place them.
is this correct?

(1. was ok)
2. yes, that's now correct.
3. no, you've swapped the angles (as in 2), but the angles were in the right place … i was just saying that the triangle would look better if the right-angle was at bottom right, instead of top left.

do you mean like this?

Sort-of.

You don't need a big red dot at the origin, provided it's clear where the origin is …

drawing the two coordinate axes (even if they're not marked as such) makes it clear that the origin is where they cross.

And you don't need arrows on the axes …

(in fact, if you do put arrow on them, you should only put the arrow on one end …

an axis only points in one direction, doesn't it? )

What I meant about the arrow was that, if you don't draw coordinate axes (so the origin isn't marked), then you must put an arrow on your answer vector.

 

[cary1234]

ok!

now i know..

and now i understand those basic parts. thanks!

im waiting for more than hours.. haha!

thank you very much.