Floating on Ice: Calculating Volume Needed to Stay Afloat

Click For Summary
To determine the minimum volume of ice needed to keep a 60 kg person afloat, the discussion emphasizes applying Archimedes' principle, which states that the buoyant force equals the weight of the displaced fluid. Participants clarify that the buoyant force should be calculated using the density of water (1000 kg/m³) rather than ice. The total downward force includes both the weight of the person and the ice, leading to the equation where the total weight equals the buoyant force. The correct volume of ice required is derived from balancing these forces, ultimately indicating a need for further calculations to arrive at the accurate volume. The conversation highlights the importance of considering both the person and the ice when calculating buoyancy.
  • #31
m x g= pice x Vice x g
 
Physics news on Phys.org
  • #32
Going back to your basic equation F(g) = F(a), the left side is the total force of gravity (acting down) and the right side is the buoyant force (acting upward). Now write out each side. You should find that your unknown Vice occurs on both sides of the equation.

If you want to create subscripts you can use the tool bar. Greek letters and other symbols can be found by clicking on the Σ symbol on the tool bar.
 
  • #33
I've been doing the way you told me But i still don't get the right answerAnd thank you for informing about subscripts :)
 
  • #34
In the equation F(g) = F(a), what did you write for F(g)? That is, how did you express the total force of gravity on the system?
 
  • #35
F= 60.0 kg x 9.81 m/s2 =588.6
 
  • #36
That's the force of gravity on the person alone. How would you express the total force of gravity on the system? The system consists of the man and the ice.
 
  • #37
917 kg +60.0 kg x 9.81 perhaps
 
  • #38
The total force of gravity is equal to the weight of the person plus the weight of the ice. Post #35 has the weight of the person. Post #31 has the weight of ice. Adding these together gives you the left side of F(g) = F(a). The right side of the equation is the buoyant force given in post #20.
 

Similar threads

  • · Replies 15 ·
Replies
15
Views
2K
  • · Replies 6 ·
Replies
6
Views
614
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 12 ·
Replies
12
Views
2K
Replies
5
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K