Question

Mark Watney begins his day 15 km West and 25 km North of his Mars Habitat. a. Set up a co-ordinate system (draw labeled axis and tickmarks showing the scale) and draw a vector representing the initial position of Mark Watney. b. Mark spends his day driving his Mars Rover towards Schiaparelli Crater and manages to make it an additional 20 km West but has to go around a hill so ended up 5 km South of his starting point for the day. Draw a vector representing Mark's total position change for the day. c. Using vector addition find Mark's position relative to the Mars Habitat. Give both the numerical description of the vector and show it on your plot.

Answer 1

Answer:

a, b) part a and b on diagram attached

c) sf = -35 i + 20 j

35 km West and 20 km North

Explanation:

For part a and b refer to the attached co-ordinate system:

Note: unit vector i is in West/East direction and unit vector j is in North/South direction.

si = -15 i + 25 j

sf-si  = -20 i - 5 j

Hence,

Mark relative position from habitat sf = si + sf/i

sf = ( -15 i + 25 j ) + ( -20 i - 5 j )

sf = -35 i + 20 j

35 km West and 20 km North