Material that sink Modeling clay. Other materials Rope Scissors Scotch tape

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1 NEMO-Workshop Floating & Sinking The workshop can be divided into two separate parts: 1. Experiments, done by Parent-child teams 2. Demonstration, given by the Explainer 1. Experiments Parent en child work together in teams. Each parent-child team is provided with a box of materials. The number of sets needed, depends on the number of partaking teams. Plastic box To perform the experiments the teams need a container filled with water. The plastic box shown in the picture serves as an water container during the experiments. After the workshop has finished, one can fit the materials inside the box. This makes storage much easier and tidy. The box was purchased at a local 'household shop' (much like Ikea, for instance). Specifications: Size: 42 x 36 x 27 Content: 30 liters. Content of box Materials that can floats See for further specification of size and weight appendix 1 2 plastic blocks 2 MDF board blocks 2 foam block 2 foam triangles 2 plywood block Jar with lid (when empty then floats) Slices of foam (floats_ Ping pong ball Material that sink Modeling clay Other materials Rope Scissors Scotch tape

2 Extra materials for experiment 7 Coins For experiment 7, teams are asked to produce two balls (equal in size and weight), of which one is solid and the other contains air in the center. From experience it can be told that participants find producing the lather ball a difficult task. The science explainer can help them by pointing them at the coins at hand. These coins provide an excellent way to add weight to the ball, without adding (too much) volume. Two clay balls The two clay balls shown in the picture should not be at hand, but should be produced by the teams themselves. However, experience has shown that this proves to be a rather difficult task. So here is how to make them: Make one solid ball of clay of about 7,5 in diameter. Weigh the ball (this should weigh in at around 264 gr.). Now take a ping pong ball, and cover it in clay, thus creating a ball 7,5 in diameter. Weigh this ball as well (this should weigh in at about 216 gr.). This leaves a 48 gr. difference between the balls, which can be made up with the coins shown above. Add coins to the lighter ball until you have reached 264 gr. Scale To be able to make the balls of clay, teams need a scale. This way they will be able to tell whether they need to add coins (weight) to the ball in order to get to the right weight. Providing each parentchild team with a scale might become quite costly, so a limited number of scales is advisable. Preferably the scale reads up to one hundredth of a gram. Extra materials for experiment 8 Polystyrene flakes For experiment 8 the teams need polystyrene flakes. These have a lot of volume, yet very little mass. They can be purchased from any hardware store. Pebbles Teams can use pebbles to give weight to the jar/container of experiment 8. As the containers at hand are not very large, pebbles proved to be the ideal material to fill them with. They add a lot of weight, are easy to come by, and quite easy to handle.

3 Extra materials for experiment 9 Container for big amount of water For experiments 9 the teams need a water container larger than the one they are given (the 30 l. plastic box). Because providing each parent-child team with a substantially larger water container proved to be a lot of work, it is advisable to set up one 'station' with a large water container. Participants will have to leave their own 'station' for this experiment, but this proved to be the easiest way. The container shown in the picture was at hand in Nemo. However, any container -as long as it is larger than the one participants are provided with- will suffice for this experiment. Specifications: 20 x 20 x 60 Extra materials experiment 10 Container for oil For experiment 10 the teams need to submerge a balloon in sunflower oil. For the same reasons described for the large water container, it is advisable to set up one station where the sunflower experiment can be conducted. To minimize messy situations as well as trouble storing the sunflower oil after the workshop, a 3 to 5 liter container is recommended. The container shown in the picture was purchased from a local household shop. Specifications: 10 x 10 x 30 Content: 3 l. Sunflower oil There should be enough sunflower oil to fill the small container described above. It can be purchased from any local supermarket. Water balloons For the sunflower oil experiment, the participants will need something small that can contain water. After numerous experiments, water balloons proved to be the easiest to fill up, as well as the easiest to purchase. Also, the lightweight material hardly adds to the weight of the object, which rules out any biased results.

4 2. Demonstration For the concluding demonstration the science explainer needs a number of objects and materials to demonstrate Archimedes' law. Below you will find what objects and materials are needed in both parts of the workshop. This list will also provide further information on how the objects were made or obtained, as well as specifications on materials, dimensions, weight, etcetera. Water container with overflow In order to collect the displaced water when conducting the experiments, a water container with an overflow is needed. This can be made by drilling a hole in a container, and fitting the hole with a tube. The tube should preferably be made from a hard material such as plastic. The length of it makes very little difference, but the angle under which it is fitted into the hole is very important. Generally; the steeper the angle, the better. To keep the tube in place, cover up the parts of the container that are 'pierced' by the tube with clay. This creates a watertight seal. Blocks For the demonstration the science explainer needs three equally sized blocks, of different materials. These blocks were cut to the right dimensions in Specifications: Size: 4 x 6 x 10 Weight: 12 gr., 180 gr. and 266 gr. respectively. Material: Foam, MDF and clay respectively. Measuring cylinder or cup In order to keep track of the volume of displaced water, the water must be collected in a marked container. For larger amounts one can use a 1 liter cup. For smaller amounts a 50 ml. cylinder is advised. Both containers were purchased from a local household store. Masking tape To keep track of the changes in water level inside the water container, one can use masking tape to mark the water surface. Each time an object is put in the water, the water level will rise and can be marked again. This masking tape can be purchased from any household- or hardware store.

5 1 Plastic Blocks were cut to the right dimensions in Size Weight Material 4 x 6 x gr. Plastic (fairly dense). 2 MDF Blocks were cut to the right dimensions in 3 FOAM Blocks were cut to the right dimensions in 4 FOAM triangles were cut to the right dimensions in Nemo's workshop 5 Plywood Block was cut to the right dimensions in 4 x 6 x 10 4 x 6 x x 10 x 14 x 4 1 x 7 x gr. MDF-board. 12 gr. Foam. 10 gr. Foam. Plywood. 6 Rope was purchased at a local hardware store. 30 m. long. 2 mm. thick. 7 Jar with lid was purchased at a local supermarket (holding peanut butter). Content: 0,3 l. Content: 0,3 l. Content: 0,3 l. 8 Plywood Board cut to the right dimensions in Nemo's workshop. Size: 1 x 10 x 13 Weight: 105 gr. 9 Plywood Board was cut to the right dimensions in Size: 1 x 6 x Weight: gr. 10 Modeling clay were purchased at a local crafts shop. Weight: 172 gr. per bar. 11 Slices of foam were cut from a larger piece of foam, Size: 0.5 x 3 Weight: 3 that came from a chemistry set (in which it was used x 5 gr. to protect the materials inside the box). 12 Scissors were purchased from a local crafts store. 13 Scotch tape was purchased from a local office supplies store. 14 Ping pong ball was purchased from a local sports store. Size: 4 diameter. Weight: 2 gr. Material: Plywood. Material: Plywood. Material: Foam.

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