Question

PLEASE, HELP been waiting nearly and hour... – Drawing a vector displacement problem, need help!
After being kidnapped and placed in the trunk of a car, you discover you are able to pry open the trunk. The GPS tells you that you're moving 35 mph in a direction 66 north of east at a location 1.33 mi west of the police station. 5 min later, you take another reading that tells you are now 2.1 mi from the police station in a direction 20 degrees east of north and are moving E at a speed of 10 mph. Find the avg. velocity and acceleration during the trip.

Answer 1

The second set of points was meaner to find because it gave them to you in polar form. Remember that polar coordinates in cartesian can be found by

x = r cos (theta)
y = r sin (theta)

But only when theta is measured from quadrant 1. If you used the 20 degrees they gave you, the cos and the sin would be switched around.


Remember that the average velocity is the change in position - that's the vector from point A to point B - over time 5 min.

The average acceleration is the change in velocities.

Whereas you can calculate displacement vector just by making a right triangle using your two points, the change in velocity is most easily done component-wise.

Hope this helps :)

Answer 2

* from the origin in quadrant 1 anticlockwise

Answer 3

Hey @AllTehMaffs I'm having trouble finding average velocity. By the way, I switches cos and sin around because I'm using 20 degrees. Could you help me out?

Answer 4

How would I use components to find the avg. velocity @AllTehMaffs

Answer 5

Kidnapped? What a horrifying question.

Answer 6

Hi. Sure. For the average velocity you need to find the magnitude of the vector that goes from from the first GPS point to the second. So