# Tomato, Salt Water & Olive Oil - Buoyancy

## Homework Statement

1. You put a tomato into a vessel of salty water - it floats. Now you pour olive oil into the same vessel. Which one of the following statements is true?

a. More of the tomato will be above the surface of the water.
b. The tomato will stay at the same height.
c. Less of the tomato will be above the surface of the water.

2. The salty water has a density of 1020 kg/m3 and the tomato a density of 950 kg/m3. Before you pour in the olive oil, what percentage of the tomato floats above the surface of the water?

3. After you pour in enough olive oil (density of 870 kg/m3) so that the top of the tomato is completely covered, what percentage of the tomato floats above the surface of the water?

2. The attempt at a solution

1. Correct answer is (a).

2. Correct answer is 6.9%.

ρ of tomato / ρ of salt water

950 kg/m3 / 1020 kg/m3

= 0.931
= 93.1%
100% - 93.1% = 6.9%

3. Not sure how to do it. Do I do the same thing for this as in #2? Please help?

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