A cube of wood 20cm on each side floats in water so that 7cm is above the surfac
ID: 1392632 • Letter: A
Question
A cube of wood 20cm on each side floats in water so that 7cm is above the surface of the water and 13cm is below.
a)What is the density of the wood? ( You must justify your answer)
b) How much force would have to be exerted on the wood to submerge it?
c) what volume of lead mass has to be placed on top of the block of wood so that it will just be totally submerged?
d)Suppose a 5kg mass of lead is now placed on top of the block of wood, how much of the wood would now be above the water?
Densities.in g/cm^3 Water=1 g/cm^3 Iron=7.8g/cm^3 Lead=11.3g/cm^3
Explanation / Answer
A)
yes the ice will melt , as the initial temperture of water and vessel is high
and the ice will melt to come to an equilibrium temperature.
B)
let the final temperature is Tf
0.10 * 1000 * (50 - Tf) + 500 * 1 *(50 - Tf) = 80 * 100 + 30 * 100 * 0.50 + 100 * 1 * Tf
Tf= 29.3 degree
the final temperature is 29.3 degree
C)
for also dropping the glass ,
0.10 * 1000 * (50 - Tf) + 500 * 1 *(50 - Tf) + 200 * 0.20 *(110 - Tf) = 80 * 100 + 30 * 100 * 0.50 + 100 * 1 * Tf
solving for Tf
Tf = 33.65 degree C
the final temperature is 33.65 degree C