Ice floating with person: why is my buoyancy calculation wrong?

[Nanu Nana]

m x g= pice x Vice x g

 

[TSny]

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 V_ice 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.

 

[Nanu Nana]

I've been doing the way you told me But i still don't get the right answerAnd thank you for informing about subscripts :)

 

[TSny]

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?

 

[Nanu Nana]

F= 60.0 kg x 9.81 m/s2 =588.6

 

[TSny]

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.

 

[Nanu Nana]

917 kg +60.0 kg x 9.81 perhaps

 

[TSny]

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.