# Homework Help: Buoyancy and Density Archimedes

1. May 10, 2012

### Koborl

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

1. a 300kg object is placed upon a block of ice what volume of ice is needed to keep the object fully above water.

2. if the object density is .94gcm ^-3 what volume of the object remains above water on ice half the size.

3. What volume of the object remains above water when the ice is fully melted.

p(water) = 1gcm^-3
p(ice) = 0.92 gcm^-3

2. Relevant equations

B = mfg
V = m/p

3. The attempt at a solution

1.
v= volume of water displaced

(denstiy of water)1000 kg/m^3* v = 300(weight of object)+ (denstiy ice)920 kg/m^3 *v
80 kg/m^3 v = 300
v = 3.75 m^3

2. ??????????

3. 6% of the object remains above water because buoyancy is .94 and water is 1??????

V = m/p

p = 0.94 g/cm3
M = 300 kg = 300000g
V = 0.31914893617021 m^3

V above water = .01914m^3

I'm fairly sure i've got question 3 all wrong though :(

Last edited: May 10, 2012
2. May 10, 2012