A student runs 30 m east, 40 m north, and 50 m west.?
(a) What is the magnitude of the student's net displacement?
a.between 0 and 20 m
b.between 20 m and 40
c.between 40 m and 60 m
(b) What is his net displacement?
direction___° west of north
- Anonymous1 decade agoFavorite Answer
So you go east 30m, then 40m north, then 50m west. When you go east you head in the +x direction 30m and when you go west, you go 50m in the -x direction, so the net x-displacement is:
-50m + 30m = -20m--->The negative sign indicates 20m net displacement to the west.
Your y-displacement is the 40m north, so now you you have a right triangle, with an unknown angle. You can use the Pythagorean theorem to solve for the magnitude of your resultant displacement vector:
Resultant displacement = sqrt(20^2 + 40^2)
To find the angle of your resultant vector use the inverse tangent function as such:
inv tan(40m/20m) = Angle of your resultant vector above the x-axis.
Hope this helps! :)
- 1 decade ago
a: c 40-60m
c: 30° west of north