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VidsEpic
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3rd time I'm posting in a day.
A skier (68 kg) starts from rest but then begins to move
downhill with a net force of 92 N for 8.2 s. The hill levels
out for 3.5 s. On this part of the hill, the net force on the
skier is 22 N [backwards]. T/I
(a) Calculate the speed of the skier after 8.2 s.
(b) Calculate the speed of the skier at the end of the
section where the hill levels out.
(c) Calculate the total distance traveled by the skier before
coming to rest.
http://www.lakeheadschools.ca/scvi_staff/childs/Gr11_physics_web/downloadable_content/unit3/textpdf3/phys11_3_5.pdf
Question 8 on the book in the link above ^
f = ma
displacement = .5 * a * t^2
v^2 = u^2 + 2as
a) a = f/m = 1.35 m/s/s * 8.2s = 11m/s (Correct according to answer key)
b) same procedure as above, simple physics, answer is 9.86 m/s, rounds to 10 m/s (Correct according to key)
c) For segment A .5*a*t^2 gives 45.5m and for segment B, v^2 = u^2 + 2as gives 32.45m,
but wait, I don't see what happens after that? The question doesn't even tell me when or if the skier comes to rest.
The answer key answer is 82m
I have 78m so far, am I missing something in the question or is there something wrong with it.
Homework Statement
A skier (68 kg) starts from rest but then begins to move
downhill with a net force of 92 N for 8.2 s. The hill levels
out for 3.5 s. On this part of the hill, the net force on the
skier is 22 N [backwards]. T/I
(a) Calculate the speed of the skier after 8.2 s.
(b) Calculate the speed of the skier at the end of the
section where the hill levels out.
(c) Calculate the total distance traveled by the skier before
coming to rest.
http://www.lakeheadschools.ca/scvi_staff/childs/Gr11_physics_web/downloadable_content/unit3/textpdf3/phys11_3_5.pdf
Question 8 on the book in the link above ^
Homework Equations
f = ma
displacement = .5 * a * t^2
v^2 = u^2 + 2as
The Attempt at a Solution
a) a = f/m = 1.35 m/s/s * 8.2s = 11m/s (Correct according to answer key)
b) same procedure as above, simple physics, answer is 9.86 m/s, rounds to 10 m/s (Correct according to key)
c) For segment A .5*a*t^2 gives 45.5m and for segment B, v^2 = u^2 + 2as gives 32.45m,
but wait, I don't see what happens after that? The question doesn't even tell me when or if the skier comes to rest.
The answer key answer is 82m
I have 78m so far, am I missing something in the question or is there something wrong with it.
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