Since the object is moving at a constant speed, we assume there is no acceleration, therefore
Total Force = mass*acceleration
Total Force =mass*0
Total Force = 0
Frictional force = 7.38 N
Total Force = Force - Frictional Force = 0
Force = Frictional Force
Force = 7.38 N
To find work we use the following formula:
Work = Force * distance
Using the coordinates given, we realize that the distance from O to A is 5 m, since the object goes from O to A and then back to O, we multiply 5 by 2, and get 10 m for the total distance (net displacement) traveled in part A.
distance = 10 m
Work = 7.38 N * 10m = 73.8 J
First find the net displacement (total distance traveled.)
The purple path from O to C is 10 m. And the return blue path can be found using the pythageoreom theorem:
√(25m+25m) = c
Therefore the net displacement is 5m + 5m + 7m = 17m
Plugging this into the work equation we get:
Work = 7.38 N* 17m = 125.46 J
Part C is also solved the same way.
Work = 7.38 N * 14 m
Part D: We learn that the force of friction is a nonconservative force, because the values are nonzero.