Physics Homework #1

[Jess]

PLEASE ANSWER BEFORE FRIDAY 6 PM EST THANKS

Two geological field teams are working in a remote area. A global positioning system (GPS) tracker at their base camp shows the location of the first team as 32 km away, 12° north of west, and the second team as 26 km away, 31° east of north. When the first team uses its GPS to check the position of the second team, what does the GPS give for the following?

(a) the second team's distance from the first team - 47 km
(b) the second team's direction from the first team, measured relative to due east
?° north of due east

>> EDIT: solved



A snowmobile moves according to the velocity-time graph shown in the drawing. What is the snowmobile's average acceleration during each of the segments A, B, and C? The scale for the time axis is 80 s per increment, and the scale for the velocity axis is 350 m/s per increment.
http://www.webassign.net/cj8/2-p-065-alt.gif

>> EDIT: solved

[Mynick]

You can found the first problem explanation here (http://answers.yahoo.com/question/index?qid=20090901004907AARdWiP)
plus it has a diagram to explain it better.

[Jess]

I looked at that already but still got the wrong answers :/

EDIT: got the right answer...sigh don't know what happened...one more to go


.......
I still can't get how to find the slope aka acceleration of Segment C :/

[Jess]

Bump. I REALLY need help on the last problem. I don't get what I'm doing wrong. Probably something stupid?

[Mynick]

Let me think a bit, im kinda rusty too i'll edit this when i get something.

I did 700/11 = 63.63
I divided by 11 because he accelerates 11s (seems 11s) since B

[Jess]

The increment is 80 s, so it can't be 11...:S

[Mynick]

I was thinking since v will increae 700 in 11 secs divifing it would give us the answer. Uhm. Dont really know then.

[Jess]

The acceleration is the slope of the velocity graph, so it's rise over run or velocity over seconds. I got A and B correct by doing that and I just don't understand why it's wrong for C

[Jess]

Another version:

A snowmobile moves according to the velocity-time graph shown in the drawing. What is the snowmobile's average acceleration during each of the segments A, B, and C? The scale for the time axis is 80 s per increment, and the scale for the velocity axis is 370 m/s per increment.

Graph is exactly the same image as in first post

The correct answer is 7.71.

I have NO idea whatsoever how they got that. It is certainly not from 740/82

...I just realized what I've been doing wrong all along. The seconds is NOT 82...since it's increments of 80, it can't be 82. Well. Duh.


EDIT: It's 96, not 82. Geez. All this time it's been staring me in the face.