Answer:
(a) work done by Jack is -2200J
(b) work done by Jill is 0
Explanation:
Given;
Initially boat's position = < 2, 0, 3 > m
Final boat's position = < 6, 0, 1 > m
change in position = < 4, 0, -2 >
Force exerted by Jack = < -440, 0, 220 > N
Force exerted by Jill = < 170, 0, 340 > N
Part (a) How much work does Jack do?
work done = force x distance
Jack's work = < -440, 0, 220 > N x < 4, 0, -2 > m
= [(-440*4) + (0*0) + (220*-2)]
= -1760 J - 440 J
= -2200J
Part (b) How much work does Jill do?
Jill's work = < 170, 0, 340 > N x < 4, 0, -2> m
= [(170*4) + (0*0) + (340*-2)]
= 680 J - 680 J
= 0
