Student Worksheet!

Student Guide for Density Simulation:                              Name: Leah Corso

(note: “sink” means stays on the bottom)

Google:   Phet Density sim

Start:    1.                                                   

              2.           Click on the first link

     3.           Click on the   button

     4.          Experiment with choosing a material:

material	S=sinker F=Floater	Density given
Wood	F	.4 kg/L
Styrofoam	F	.15 kg/L
ice	F	.92 Kg/L
brick	S	2.0 kg/L
aluminum	S	2.7 kg/L

Put the materials in the correct boxes

5.    Try to get aluminum to float.      Talk with your partner about this possibility- can you change the mass of the aluminum block without changing the volume of the aluminum block?  You can not change the mass. If something has increased mass it will have increased volume.

6.    What do you and your partner notice about the density triangle at the bottom of the box?  Why do you think this does or does not move? There is more molcules packed into that space. Volume and mass will not affect density.

                                            

7.                                 How does the density of aluminum (2.70 kg/L)  help explain what you see?

It shows me how it affects the space that is being taken up by the water and block in the tank

Frame:  The aluminum will sink in the water because the density of the aluminum is 2.70kg/L and the density of water is  1 kg/L_.  We have learned that an objects density will not change despite changing volume and mass.

8.    Density  = ----------       “_______ over ______ equals _______________” Mass divided by volume equals density

In the “Blocks” box, click on Mystery:

Test the boxes in the water- just drag and drop!!!

  

When you have determined which ones sink and float, fill in the data table for each box. 

Sample	Starting volume of water (A)	volume of water and block (B)	Volume of block alone (difference B-A)	Mass (kg)	Density (kg/L)	What is it most likely made of? (hint: use Show Table for help)
A	100-L	103.38	3.38	65.14	19.3	Gold
B	100-L	100.64	.64	.64	1	Water
C	100-L	104.8	4.08	4.08	1	Water
D	100-L	103.10	3.10	3.1	1	Water
E	100-L	101.0	1	3.53	3.53	Dimond

9. 
 Look closely at green box C and red box D and discuss your observations.

 List three observations you made while comparing the two boxes.

1st observation Green box C is slightly larger

2nd observation Box C has a larger mass by .98 kg

3rd observation Both are water

10. Dear Students,

I am going to build a boat.  My partner says I cannot put a refrigerator and a television in my boat because that would make it too heavy-and the boat might sink. Then we would be swimming with the sharks!!!!

What would you advise me to tell my friend? Is she right or wrong?  Be sure to give me some evidence based on what you learned from the boxes or other places in this activity.

__________________________________________________________________________________________________________________________________________

…you can write on the back if you need more room to write!       Signed, your teacher

The first step is to measure the boat to understand how much volume is there. The next step would be to calculate the density of each object. If one object has a greater density the best thing to do would be to leave that object behind and only take one. However if both have the same density it would be acceptable to take them on the boat. Looking at boxes C and D they both have different masses but still carried the same density. This can be applied to your appliances.