Lydia's Science Fair Project: Floating Fruit

Lydia was really excited about her science project for our annual homeschool science fair. She had the idea one night while she was getting ready for bed and she wrote down all of her thoughts and notes on a scrap piece of paper by her bed. She planned and prepped for her project independently and her project turned out really well. She decided that she wanted to title her project "Floating Fruit" and test three kinds of fruit in three types of liquid cut in three different ways. 

-Apple, Pear, Mango
-Water, Sprite, Orange Juice
-Whole, Half, Pieces. 

She tried each fruit in each different size (whole, half, pieces) in each of the liquids and recorded her data. We were surprised to see that some fruits floated differently in each liquid and that the size did matter. I loved watching her take ownership in this project and we enjoyed working together on such a fun experiment. 

Floating Fruit 

By Lydia Peaden, 4th grade, Age 9 

February 2022 

Question: Would fruits float differently if they were placed in three different liquids and cut in three different ways? 

Hypothesis: I think that apples will float best whole in water; mangos will float best half in sprite, and pears will float best half in orange juice. 

Materials: 

3 Mangos, 3 Apples, 3 Pears 

3 Basins 

1 Gallon each:  Water, 7-Up, Orange Juice 

Timer 

Research: Different fruits sink or float depending on their density. Density is how heavy an object is compared to it’s volume. Water has a specific density, too. When you place a fruit in water (or other liquid)the one with the lowest density will float (or rise to the top). 

Experiment: Step 1: Cut one of each fruit in half, one in pieces, and keep one of each whole. Step 2: In one basin pour one gallon of orange juice, in another one gallon of 7-Up and in the last, pour one gallon of water. Step 3: Using one group at a time, place into each liquid for three minutes. Observe how well each fruit floats and record. 

Conclusion: In conclusion, I found that apples floated best in all the liquids because they are the least dense. Pears and mangos are more dense than water, but when cut they were less dense than 7-Up or Orange Juice. 

Report:

My name is Lydia Peaden and my science project is called “Floating Fruit”. My question was “if three fruits were cut up in three ways and put in three different liquids, would they float differently?” My purpose was to discover the answer. 

My hypothesis was: Apples would float best whole in water. Mangos would float best half in sprite.  And pears would float best half in orange juice. 

As I completed my experiment I observed that although apples floated in every liquid and every size, mangos and pears floated differently in different liquids and sizes. I was really surprised when the mango floated in orange juice after it was cut, even though it did not float whole. 

In my research I learned that different fruits sink or float depending on their density. Density is how heavy an object is compared to its volume. Fruits have different densities and water, 7-up, and orange juice have specific densites, too. When you place a fruit in liquid, whichever has the lowest density will rise to the top. For example, the whole mango is more dense than the water, which makes it sink to the bottom. (see data chart). The apple is less dense and so it floats to the top. Mangos and pears floated best half and in pieces in Orange Juice and in 7-up. I also believe that one of the reasons the whole pear and whole mango floated in the 7-Up was because of the bubbles that gathered on the fruit – those bubbles helped hold it up, even though their densities may have been greater than the liquid. 

In conclusion, I found that apples floated best in all the liquids because they are the least dense. Pears and mangos are more dense than water, but when cut they were less dense than 7-Up or Orange Juice. I enjoyed this project and learned about density and why and how different fruits float.