# 2-D Kinematics

1. Sep 15, 2006

### Joules23

The 1994 Winter Olympics included the aerials competition in skiing. In this event skiers speed down a ramp that slopes sharply upward at the end. The sharp upward slope launches them into the air, where they perform acrobatic maneuvers. In the women's competition, the end of a typical launch ramp is directed 63° above the horizontal. With this launch angle, a skier attains a height of 11.7 m above the end of the ramp. What is the skier's launch speed?

i dont know where to begin with this since so little info is given,

2. Sep 15, 2006

### NateTG

This is mostly a 1-D problem.

3. Sep 15, 2006

### Joules23

ok, i have the 3 sides of the traingle, but i do now know what to do with them, 13.13, 11.7, 5.96

4. Sep 15, 2006

### NateTG

Here's a slightly easier problem you could solve first:
If I throw a ball straight up, how fast do I need to throw it so that it goes up 11.7 meters?

5. Sep 15, 2006

### Joules23

EDIT: u are right it is too high.. 15.14m/s is the right one i think

Last edited: Sep 15, 2006
6. Sep 15, 2006

### NateTG

That number seems a bit high ....

Now, let's say that I throw the ball at a 45 degree angle with horizontal instead of straight up - how fast do I have to throw it?

7. Sep 15, 2006

### Joules23

i have no idea

8. Sep 15, 2006

### Joules23

9. Sep 15, 2006

### NateTG

What's the vertical component of the velocity of the ball when I throw it?

10. Sep 15, 2006

### Joules23

10.7m/s ??

11. Sep 15, 2006

### NateTG

It would only go up about 5m if that was the vertical component.

12. Sep 15, 2006

### Joules23

Vy of the ball at 45degrees or Vy of the ball thrown straight up??? wow if every problem is going to take me this long i think ill be done next month
can you give me a forumla or something for the actual problem

Last edited: Sep 15, 2006
13. Sep 15, 2006

### Joules23

anyone? im completely lost

14. Sep 15, 2006

### NateTG

The way I would do this problem is:
1. Figure out the vertical component of the skiers velocity at the end of the ramp.
2. Use trig to determine the total velocity.

15. Sep 15, 2006

### Joules23

How would i find the vertical component of the skiers velocity, when it does not give the velocity

IS 11.7 the vertical component?

Last edited: Sep 15, 2006
16. Sep 15, 2006

### NateTG

The horizontal and vertical components are independant.