Question

The force acting on a particle varies as shown in Figure P7.14. Find the work done by the force on the particle as it moves (a) from x = 0 to x= 8.00 m, (b) from x= 8.00 m to x = 10.0 m, and (c) from x = 0 to x = 10.0 m.Did I do this right? See above.

Answer 1

a) The work done by the force on the particle as it moves from x = 0 to x = 8.00 m is

the area under the graph.

Therefore the work done, Wx=0 to 8 m = (1 /2 ) base x height

                                                         = (0.5)(8 m)(6 N)

                                       Wx=0 to 8 m  = 24 J

________________________________________________________________________

b) The work done by the force on the particle as it moves from x = 8.00 m to x = 10.0 m is

the area under the graph.

Therefore the work done, Wx=8m to 10m = (1 /2 ) base x height

                                                            = (0.5)(2 m)(-3 N)

                                      Wx=8m to 10m   = - 3 J  

_________________________________________________________________________

c) The work done by the force during x = 0 m to x = 10.0 m is given by

Wx=0 to 10m   = Wx=0 to 8 m + Wx=8m to 10m

                    = 24 J + ( - 3 J)

                    = 24 J - 3 J

Wx=0 to 10m   = 21 J