NationStates Jolt Archive

last question i promise

http://i26.photobucket.com/albums/c144/slicknick727/vectors2.jpg

the question:
http://i26.photobucket.com/albums/c144/slicknick727/question.jpg

i tried to find the x component by doing cos(15)=ax/2 and got 1.93, but this is the wrong answer

Interesting one. Think of it as an entertaining puzzle, not a chore. Learn to love the challenge. You will find the hours fly by. :)

wouldn't you be using cos or sin or whatever of 30 and 60? 45-15= 30 and 90-30=60

... making the answers root 3 and 1.

wouldn't you be using cos or sin or whatever of 30 and 60? 45-15= 30 and 90-30=60

im sorry i dont really understand. maybe the problem is the fact that i dont know exactly whree to place the a(parallel) and a(perpendicular) vectors

is this how theyre placed?

http://i26.photobucket.com/albums/c144/slicknick727/abectors.jpg

Well... think about it... I've given you the answers. Try and figure out how i got them. I've even told you how to get the angle you need to solve the problem. If I tell you anymore then you won't learn anything.

Draw a line from the centre of the circle, through the car, and out of the side.

That's one component.

Now draw a line at 90 degrees to that one, through the car lengthways.

That's another component.

EDIT: I think you need to revisit your terminology here, and judging by your difficulties with the constant acceleration equations, go through the problem-solving method with your teacher.

Well... think about it... I've given you the answers. Try and figure out how i got them. I've even told you how to get the angle you need to solve the problem. If I tell you anymore then you won't learn anything.

thanks man, ill see how you got those

is this how theyre placed?No. The tangent is the line in which the car is pointing towards. It's perpendicular is 90 degrees to that. For heavens sake those lines aren't even perpendicular.

No. The tangent is the line in which the car is pointing towards. It's perpendicular is 90 degrees to that. For heavens sake those lines aren't even perpendicular.
That's what I meant about terminology. There is really no hope of solving anything if people don't know what the tools are called.

o ok, ill try again

like this?
:rolleyes:

One line is drawn for you. The 45 degree line. The one at 45 degrees to the horizontal. Extend it through the car out of the circle. There's your perpendicular. The tangent is at 90 degrees, lying along the car's long axis.

hmmm so it would be like this right

http://i26.photobucket.com/albums/c144/slicknick727/vectors2a.jpg

hmmm so it would be like this right
That's more like it.

now, i know a perpendicular would be 1.73 because (cos(30))(2)=1.73, but would it be a negative or positive number since it is ponting downwards

That's more like it.

thanks

now, i know a perpendicular would be 1.73 because (cos(30))(2)=1.73, but would it be a negative or positive number since it is ponting downwards
You have no origin to relate to... so the're magnitudes really...