# Homework Help: Angel of inclination :-)

1. Sep 3, 2008

### chronie

1. The problem statement, all variables and given/known data / attempt

I have to find the angel of inclination. I have a slide forming a triangle. We measured two points in the slide a meter apart. those two points are 23cm in one point and 35cm in another. All together it has a height for 58cm. However, I have no clue how to find the angle of inclination. I know I should use either sin or tan but I don't know how I plug in the values

Attached is a picture.

much thanks,

Chronie

http://img295.imageshack.us/img295/782/49775363zx5.th.jpg [Broken]

Last edited by a moderator: May 3, 2017
2. Sep 3, 2008

### Astronuc

Staff Emeritus
It is not too clear from the picture, but are the two lengths 23 cm and 35 cm elevations of points on the slide above the horizontal, and the two points are 1 m apart as measured along the horizontal?

Think about the relationship between tan $\theta_i$, where $\theta_i$ is the angle of inclination, and the legs of triangles with heights of 23 and 35 cm. If the 23 cm leg is at distance x from the vertex, i.e. where the slide intersects with the horizontal (ground, or reference plane), what is the distance to the 35 cm leg.

Think of similar triangles sharing a common horizontal base, vertex and hypotenuse.

3. Sep 4, 2008

### chronie

So I should take the difference of distance between the two positions.

That gets me 12. Should I then make a triangle and use .12m as my hypotenuse and 1m as my other side and just take the tan inverse of that?

4. Sep 4, 2008

### Astronuc

Staff Emeritus
Well, the 0.12 m would be the vertical leg and 1 m would be the other leg, but if one finds the tan-1 of the ratio (0.12/1), that would give the angle of inclination.

5. Sep 4, 2008

### chronie

ok thank you Astronuc,

I'm new to my college physics classes and some easy things stump me!

SOLVED