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This is the only question in my physics section of projectiles I am having trouble with

http://img59.imageshack.us/img59/8373/picturen.jpg [Broken]

A skilled skier knows to jump upwards before reaching a downward slope. Consider a jump in which the launch speed is vo = 10 m/s, the launch angle is theta = 9.0 degrees, the initial course is approximately flat, and the steeper track has a slope of 11.3 degrees. Figure 4-45a shows a prejump that allows the skier to land on the top portion of the steeper track. Figure -45b shows a jump at the edge of the steeper track. In Fig. 4-45a, the skier lands at approximately the launch level.

(A) In the landing, what is the angle phi between the skier's path and the slope? In Fig. 4-45b, (b) how far below the launch level does the skier land and (c) what is phi? (The greater the fall and greater phi can result in a loss of control in the landing)

Skier:

Vi: 10m/s

Angle: 9.0 degrees

Vix: 10cos9.0

Viy: 10sin90

Track:

Slope: 11.3 degrees

At this point, I really have no idea what I'm even doing.

I can't even start because I don't know the time it would take for the skier to hit the ground, or the horizontal distance he would have.

Since the equation doesn't have a flat plain, I can't use the Range formula. Since I have no x and y coordinates, I can't really use the trajectory formula, and even if I could, how does it make up for knowing when I intersect and inclined plane? I don't know it's x and y components at all and have no way to break them up.

Also, (a) has an answer of 2.3 mainly because I assume that:

Since I think it's referring to Fig A, the skier would be landing at the same angle he launches at, and since the slopes angle is 11.3... The difference (phi) would be 2.3.

Anyone have a better explanation for (a)?

Anyone care to help me with (b) and (c)?

What I wanted to try and do is use trajectory:

o = theta

y = (tan o)x - ((|g|*x^2)/(2vi^2*cos^2o))

I would try to be solving for the y value, but I don't know the x value at all, so I'd get stuck when trying to solve it anyway if I number crunch that down.

Again, I could solve for the x value EASILY if I knew time using the simple Vix*t = d, but I don't and can't find t out, so I can't solve for the horizontal distance. Also, since the plain isn't horizontal as I said before, i can't use the Range formula.

**(This is ranked as the hardest question in this section of my text, please cut me some slack :P)**, because I have no idea how I would go about finding the intersection point of the skier with the slope. The reason I don't know how to do this is because I don't know how to turn the angle of depression of the slope versus the horizontal into something I can use.http://img59.imageshack.us/img59/8373/picturen.jpg [Broken]

A skilled skier knows to jump upwards before reaching a downward slope. Consider a jump in which the launch speed is vo = 10 m/s, the launch angle is theta = 9.0 degrees, the initial course is approximately flat, and the steeper track has a slope of 11.3 degrees. Figure 4-45a shows a prejump that allows the skier to land on the top portion of the steeper track. Figure -45b shows a jump at the edge of the steeper track. In Fig. 4-45a, the skier lands at approximately the launch level.

(A) In the landing, what is the angle phi between the skier's path and the slope? In Fig. 4-45b, (b) how far below the launch level does the skier land and (c) what is phi? (The greater the fall and greater phi can result in a loss of control in the landing)

## Homework Statement

Skier:

Vi: 10m/s

Angle: 9.0 degrees

Vix: 10cos9.0

Viy: 10sin90

Track:

Slope: 11.3 degrees

## Homework Equations

At this point, I really have no idea what I'm even doing.

## The Attempt at a Solution

I can't even start because I don't know the time it would take for the skier to hit the ground, or the horizontal distance he would have.

Since the equation doesn't have a flat plain, I can't use the Range formula. Since I have no x and y coordinates, I can't really use the trajectory formula, and even if I could, how does it make up for knowing when I intersect and inclined plane? I don't know it's x and y components at all and have no way to break them up.

Also, (a) has an answer of 2.3 mainly because I assume that:

Since I think it's referring to Fig A, the skier would be landing at the same angle he launches at, and since the slopes angle is 11.3... The difference (phi) would be 2.3.

Anyone have a better explanation for (a)?

Anyone care to help me with (b) and (c)?

**Further analysis**:What I wanted to try and do is use trajectory:

o = theta

y = (tan o)x - ((|g|*x^2)/(2vi^2*cos^2o))

I would try to be solving for the y value, but I don't know the x value at all, so I'd get stuck when trying to solve it anyway if I number crunch that down.

Again, I could solve for the x value EASILY if I knew time using the simple Vix*t = d, but I don't and can't find t out, so I can't solve for the horizontal distance. Also, since the plain isn't horizontal as I said before, i can't use the Range formula.

**More work is below**
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