# A child pulls a wagon by the handle along a flat sidewalk.

#### SilentWind12

1. Homework Statement
A child pulls a trolley by the handle along a ﬂat sidewalk. She exerts a force of 80.0 N at an angle of 30.0° above the horizontal while she moves the wagon 12 m forward. The force of friction on the trolley is 34 N.

2. Homework Equations
(a) Calculate the mechanical work done by the child on the trolley.
(b) Calculate the total work done on the trolley

3. The Attempt at a Solution
W=F(cos)
80 cos(30)

W=Fcosdeltad
W=80 N(cos30)(12)
=148J

b)Idk how to do it.

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#### haruspex

Science Advisor
Homework Helper
Gold Member
2018 Award
W=80 N(cos30)(12)
=148J
Try that last step again, taking note that it is 30 DEGREES.
For b), what else is doing work on the trolley? How much work? Positive or negative?

#### NascentOxygen

Mentor
(b) Calculate the total work done on the trolley
This could be worded: Calculate the net work done on the trolley.

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