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 travelled 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 [Broken]

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

b) same procedure as above, simple physics, answer is 9.86 m/s, rounds to 10 m/s

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

I have 78m so far, am I missing something in the question or is there something wrong with it.

**1. The problem statement, all variables and given/known data**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 travelled 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 [Broken]

Question 8 on the book in the link above ^

**2. Relevant equations**f = ma

displacement = .5 * a * t^2

v^2 = u^2 + 2as

**3. 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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