Let’s do some kitchen experiments to see what may surprise you about what sinks or floats!
What you will need:
- Fruits and vegetables, including some with and without thick peels or rinds and some heavy and light ones. Examples: banana, orange, grapes, apple, bell pepper, potato, peas, zucchini;
- A large bowl or tub;
- Knife or knives;
- Optional: Scale, cans of diet and regular soda, salt, egg
Here’s what to do:
- Fill your bowl or tub with enough water to cover the biggest produce.
- Examine your items and compare their sizes, shapes and weights.
- Do some feel solid or hollow?
- Which ones do you think will sink or float in water?
- Test your predictions by placing each item in the tub to see if it sinks or floats.
- Does removing a rind or peel change the buoyancy?
- Does ripeness affect how items sink or float?
- What happens when you cut the food into smaller pieces?
Take it further:
- Does a can of regular soda float differently than a can of diet soda?
- What about other diet and regular drinks?
- Use salt to test how making water denser affects buoyancy.
- Fill two wide and tall glasses (big enough around to easily hold an egg) about half full of water.
- Dissolve 4-5 tablespoons of salt in one of the glasses.
- Try to float an egg first in the plain water then in the salty water.
- What do you notice?
- What about trying to float thin slices of potatoes or other produce in either glass?