(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Fluid displacement

This has been bugging me. Any help will be much appreciated. Thanks.

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

A 355 mL soda can is 6.2 cm in diameter and has a mass of 20 g. Such a soda can half full of water is floating upright in water. What length of the can is above the water level?

The answer is 5.22 cm but I can't reach that answer.

2. Relevant equations

Bouyant force = density(given by rho) * g * volume displaced

Density of water = 1000 kg/ cubic meter

3. The attempt at a solution

mass of water inside the can: 355/2 mL * 1kg/L = 0.1775 kg

mass of water inside the can plus the can itself = 0.1975

From the bouyant force equation, mg = rho * g * volume displaced

m = rho * volume displaced

volume displaced = m/rho = .1975 kg /(1000 kg/(M^3)) = 0.0001975 M^3

The area of the can's top is (3.1 cm)^2 * pi = 30.19 cm^2 = 0.003019 M^2

volume = area * x where x is the depth to which the can has sunk into the water. Which I reason should also be the height of the part sticking out of the water since the can is half full.

0.0001975 M^3 = 0.003019 M^2 * x

x = 0.0654 M = 6.54 cm

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Fluid displacement

**Physics Forums | Science Articles, Homework Help, Discussion**