Hw 8 force 2
here is a linearly variable force problem.
question 1
a land-sled is 100 kg in mass. it rides on a flat ground whose coefficients of friction are 0.70 for
kinetic and 0.80 for static. the land-sled is propelled by an engine that pushes the sled with on
to 2000 n linearly over a total time of 20 seconds in the horizontal direction. here is a plot of the
engine's force on the sled. ignore the fact that the sled gets lighter as fuel is consumed.
engine
asled
2000n
20 s
20 s
.
a. taking friction into account, what does the acceleration function of the sled look like? sketch it
with labels and units on the graph given above?
b. write down the acceleration function as a function of time along with the domain in which this
function is valid. attach to any constant its unit as well.
c. what are the equations of motion for this situation?
d. if the sled starts at rest, what is the velocity of the sled at 20 seconds?
e. what is the displacement of the sled over this 20 seconds?
here is a spring force problem