A submarine is a vessel that can submerge under water. The first recorded working submarine was invented in 1620 by Cornelis Drebbel, which was actually a leather-covered rowboat, that managed descend 15 feet. By the 1970’s, a design called ballasts that utilized water tanks to assist in achieving the desired depth while in operation. This key component, created by English carpenter Jay Day, helped birth the advancements that we see in our underwater ships till this day today.
EHA Activity Book Definitions:
Supplies from EHA Science Box:
- 2-liter soda bottle
- standard sized water bottles
- Metric measuring cup
- Permanent marker
- 3 rubber bands
- Discuss the definitions of a submarine and ask the students the green description in their EHA Activity Book
- Rudder: A flat movable piece of wood or metal attached to the sub and used for steering.
- Propeller:a device having a revolving hub with radiating blades, used to move the sub.
- Vertical Screw: used to help move the submarine down
- Safety Weight: used to help weigh the submarine down
Ask students to draw a picture of their submarine
- Cut off the bottom half of the 2-liter bottle
- In “U” shapes cut the bottom of the liter bottle so you have 5 separate curved blades this will become your propeller
- Drill a hole into the center of the standard sized water bottle cap
- Also drill a hole into the center of your propeller and another half an inch from the center hole
- Using scissors cut a small circle the size of the standard water bottle cap this will become your washer
- With a pen make a hole in the center of your washer that is big enough to fit the tip if a paper clip
- Straighten one end of the paper clip and feed it through the hole in the top of the bottle cap, then through the washer, and finally through the center hole in the propeller (making sure the propeller fins are facing down ward)
- Bend the inside end with the needle-nose pliers, looping it through the second off-center propeller hole to secure the paper clip and two pieces together
- With the permanent marker and measuring cup mark the standard water bottle with the measurements (20 mL, 40 mL, 60 mL…)
- Drill two small holes in the bottom of the water bottle, just like the holes in the propeller—one in the center and one slightly off-center
- Straighten one end of another paper clip and insert the straight end through the hole of the standard water bottle, from the mouth of the bottle into the centered hole at the end of the water bottle
- Bend the end of the water bottle back into a hook with the pliers
- Hook a one end of the rubber band onto the paper clip hook inside the water bottle submarine and the other to the paper clip hook inside the bottle cap propeller
- Place the ruler perpendicular and so it is just centered to the submarine. Attach it with two rubber bands that form an “X” around the bottle and the ruler( this will be your stabilizing fin)
- Using the waterproof sealant make sure that the paper clip holes are fully sealed and leaving for it to dry
- Fill your submarine with different amounts of air and water using the marks you made earlier. Starting at 0 mL, test each mark for buoyancy
- Encourage children to write down the results to compare later
This experiement explains how a submarine moves up and down with differnt amounts of pressure. The propeller alsos the submarine to move forward, but without the ruler which acts as a stabalizing fin the submarine would just be a spinning tube. The stabilizing fins resist spinning by adding a force of friction, which allows the propeller to push the submarine forward.