A skateboarder of mass 70kg pushes horizontally against the ground for 1.0s. The horizontal force exerted on the skateboarder varies with time as listed in the table.
Time t (s)
0.0
0.2
0.4
0.6
0.8
1.0
Force F (N)
0
140
220
220
140
0
Positive force points in the forward direction. Neglect all other horizontal forces.
(a) Calculate the total impulse delivered to the skateboarder during the 1.0s push.
(b) Determine the skateboarder’s change in speed over this interval.
(c) The skateboarder was initially at rest. Calculate the skateboarder’s final speed at t=1.0s.