Deciding what Angle to use....HELP PLEASE !!

[jmcpherson82]

The question is this:

A hiker sets out on a trek heading (N35degreesE) at a place of 5.0 km/h for 48.0 mins. He then heads west at 4.5 km/h for 40.0 min. Finally, he heads (N30degreesW) for 6.0 km, until he reaches a campground 1.5 hours later.

A) Find his total displacement using vector components.

SO, i used Ax = 4.0 cos 35degrees = 3.27

Ay = 4.0 sin 35degrees = 2.29

Then I looked at the answers and it said I should have used the angle 55 degree angle instead of the 35. How do I figure out when to use which angle?

[FizziksGuy]

Hi!

It depends on what you mean by N35degreesE. If you mean 35 degrees north of east, I would find Ax as 4.0cos(35) = 3.28 km. If you mean 35 degrees east of north, the angle with the horizontal would be 55 degrees. Based on what you're telling me, I imagine N35degreesE is being used to represent 35 degrees east of north. Therefore, this would look similar to the diagram below:

[ATTACH=CONFIG]431[/ATTACH]

Does this help with your problem?

Make it a great day!

Dan

[jmcpherson82]

Thank you very much! This helped a lot