# Homework Help: Acceleration in 2 component directions

1. Dec 31, 2013

### get_physical

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

Find acceleration of 100kg ship using a component solution.

2. Relevant equations

Fnet = ma

3. The attempt at a solution
break into x and y components? so that Fnet for x = 150cos20 + 300cos30 = 100a and so a = 4.01 in x direction.

Fnet for y = 150sin20+ 300sin30 = 100a and so a = 2.01 in y direction.

And the mg = buoyant force?

Not sure if I'm doing this right..

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2. Dec 31, 2013

### Staff: Mentor

You did the x direction correctly, but not the y direction. The second term should be -300 sin 30. There is no need to do the z direction, since the problem statement is implicitly not asking for that.

Chet

3. Dec 31, 2013

### get_physical

If i do -300 then I get a negative force in the y component.... does that mean the boat is moving in the south direction (south east direction?)

4. Dec 31, 2013

### Staff: Mentor

No. It means it's accelerating in that direction.

5. Dec 31, 2013

### get_physical

oh yes a negative acceleration in the y component and a positive in the x component. does that mean it is going to get straigther and straighter in the x direction?

6. Jan 1, 2014

### Staff: Mentor

What makes you think that?

7. Jan 1, 2014

### get_physical

because the acceleration is decreasing in the y component. Doesn't that mean velocity is going to become 0 in the y component? And since it's + in the x component, then it will be eventually only have velocity in the x component?

8. Jan 1, 2014

### Staff: Mentor

No. It just means that the velocity in the y direction will become zero and then negative. As time progresses, it will become even more negative.