# Will the scuba diver sink or float

1. Oct 29, 2013

### rmiller70015

1. The problem statement, all variables and given/known data
A scuba diver and her gear displace a volume of 65.0L and have a total mass of 68.0kg. What is the buoyant force on her and will the diver float or sink.

2. Relevant equations

FB=pFVg

3. The attempt at a solution
The first thing I did was find the weight of the diver as w=mg=68.0kgX9.8m/s2=670N
Then I tried to find the buoyant force using archemedes' principal (FB=pH20Vg
I used the given density as 103 kg/m3, the volume of water displaced is 65.0L, which I converted to m3 by using the factor of 103L/1m3 to get 6.5X104m3. The equation then becomes
(103kg/m3)(6.5X104m3)(9.8m/s2)
and I get 6.4X108N, which is greater than mg, so the diver would float.

I'm wondering if this is correct or not

Edit: Forgot to mention, I'm not too concerned with sigfigs, as long as the answer is withing a reasonable variance the teacher will give me credit.

2. Oct 29, 2013

### Hollumber

That buoyant force is awfully large. Check your L to m^3 conversion

3. Oct 29, 2013

### Staff: Mentor

How much does 65L of water weigh?

4. Oct 29, 2013

### Staff: Mentor

Salt water, or fresh water?

Not that it matters much in this case, but it matters when you dive.

5. Oct 29, 2013

### Staff: Mentor

Good point!

6. Oct 29, 2013

### SteamKing

Staff Emeritus
If there are 1000 L in 1 m^3, how can 65 L = 65000 m^3?

That's the amount of water displaced by a large ship.