A box rests on a horizontal, frictionless surface. a girl pushes on the box with a force of 17 n to the right and a boy pushes o
n the box with a force of 13 n to the left. the box moves 3.5 m to the right. find the work done by (a) the girl, (b) the boy, and (c) the net force.
1 answer:
Refer to the diagram shown below.
The net force acting on the box is 17 - 13 = 4 N to the right.
The box moves on a friction surface by 3.5 m to the right.
By definition,
Work = Force x Distance.
(a) The work done by the girl is
W₁ = (17 N)*(3.5 m) = 59.5 J
(b) The work done by the boy is
W₂ = (13 N)*(-3.5 m) = - 45.5 J
(c) The work done by the net force is
W₃ = (4 N)*(3.5 m) = 14 J
Note that W₃ = W₁ + W₂
Answers:
(a) 59.5 J
(b) - 45.5 J
(c) 14 J
The net force acting on the box is 17 - 13 = 4 N to the right.
The box moves on a friction surface by 3.5 m to the right.
By definition,
Work = Force x Distance.
(a) The work done by the girl is
W₁ = (17 N)*(3.5 m) = 59.5 J
(b) The work done by the boy is
W₂ = (13 N)*(-3.5 m) = - 45.5 J
(c) The work done by the net force is
W₃ = (4 N)*(3.5 m) = 14 J
Note that W₃ = W₁ + W₂
Answers:
(a) 59.5 J
(b) - 45.5 J
(c) 14 J
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