Answer:
-15Nm
Explanation:
Work is said to be done when a force causes an object to change its position.
Workdone = Force × Distance
Given the force (−2i+2j+3k)N
Since the body moves from point (−5,4,3) to the point (−2,13,−6), we will take the difference of both points to get the distance covered.
The difference will be final point (-2,13,-6) minus initial point (-5,4,3) i.e (-2,13,-6) - (-5,4,3) = (3,9,-9)
This point can be represented vectorially as (3i+9j-9k)meters
Work done = (−2i+2j+3k)×(3i+9j-9k)
Note that i.i = j.j = k.k = 1, the multiplication of different components will give "zero"
Work done = (-2×3)+(2×9)+(3×-9)
Work done = -6+18-27
Work done= -15Nm
