# Vectors acting on a mass on an incline

1. Nov 12, 2007

### fgarcia08

[SOLVED] vectors acting on a mass on an incline

hey guys! well i have this lab report due tomorrow and there is one part that i'm missing. For the discussion part i have to "draw and label the vectors acting on a mass resting on an incline" you know like mg and FN and all that fun stuff but i don't really know where they go

help would be so appreciated...

2. Nov 12, 2007

### fliinghier

3. Nov 12, 2007

### fgarcia08

hey guys! well i have this lab report due tomorrow and there is one part that i'm missing. For the discussion part i have to "draw and label the vectors acting on a mass resting on an incline" you know like mg and FN and all that fun stuff but i don't really know where they go

help would be so appreciated...

there its black....

4. Nov 12, 2007

### fliinghier

well do you know which directions Fn, Fg and Ff act in relation to the incline?

5. Nov 12, 2007

### fgarcia08

well i remember just fn goes up on the y axis in relation to the incline and fg down but there's another one its fg cos or sin then the "o" with the line halfway through it and thats the one that i don't know where to put... do u know?

6. Nov 12, 2007

### fliinghier

Fg actually goes straight down in relation to the object, not along the y-axis. the other vector is there, and is equal to (mu)Fn

7. Nov 12, 2007

### fgarcia08

oh okay now i get it its fG because of gravity so its straight down right? and then the (mu) Fn is the other one that i was talking about?

8. Nov 12, 2007

### fliinghier

yes. i guess you have not learned about friction yet then?

9. Nov 12, 2007

### fgarcia08

yes i have its the one that goes opposite the umm gosh i forget the name

10. Nov 12, 2007

### fliinghier

it is perpendicular to the normal, and parallel to the surface.

here's a hint: is the mass accelerating? what does the net force need to be?

11. Nov 12, 2007

### fgarcia08

oh okay so now i need to know what to draw for that part. and fnet needs to be the acceleration times the mass right? that sounds familiar isn't that a formula?

12. Nov 12, 2007

### fliinghier

an object at rest has acceleration = ?

13. Nov 12, 2007

### fgarcia08

false an object at rest doesn't have acceleration because acceleration is the difference of final and initial velocity divided by time and if its at rest its not going anywhere

14. Nov 12, 2007

### fgarcia08

so there is no velocity to begin with

15. Nov 12, 2007

### fliinghier

there is no velocity in the end either. there are only three forces, and you need to draw them in. you already said that Fg is straight down, while Fn is perpendicular to the grade and Ff is parallel.

16. Nov 12, 2007

### fgarcia08

so thats it im done...thank you very much