Answer:
a) The work done by the force is 720 joules, b) The power supplied by the force is 138 watts.
Explanation:
a) Since force is uniform and parallel to the direction of motion, the work ([tex]W[/tex]), in joules, done by the force ([tex]F[/tex]), in newtons, is defined by this formula:
[tex]W = F\cdot s[/tex] (1)
Where [tex]s[/tex] is the travelled distance, in meters.
If we know that [tex]F = 60\,N[/tex] and [tex]s = 12\,m[/tex], then the work done by the force is:
[tex]W = F\cdot s[/tex]
[tex]W = (60\,N)\cdot (12\,m)[/tex]
[tex]W = 720\,J[/tex]
The work done by the force is 720 joules.
b) And an expression for the power supplied by the force ([tex]\dot W[/tex]), in watts, is concieved by differentiating (1) in time:
[tex]\dot W = F\cdot \dot s[/tex]
Where [tex]\dot s[/tex] is the speed of the wagon, in meters per second.
If we know that [tex]F = 60\,N[/tex] and [tex]\dot s = 2.3\,\frac{m}{s}[/tex], then the power supplied by the force is:
[tex]\dot W = F\cdot \dot s[/tex]
[tex]\dot W = (60\,N)\cdot \left(2.3\,\frac{m}{s} \right)[/tex]
[tex]\dot W = 138\,W[/tex]
The power supplied by the force is 138 watts.
