Measure of the density of an irregular object The purpose of this science lab is to measure the density of an irregular object

Irregular object (with a hook above); 20 ml of water; Beam balance; Beaker; 200 ml graduated cylinder; Dropper.

First of all we have found the mass of our irregular object with the beam balance: we putted our object in one of the two plate and a load on the other. We have tried many times before find the perfect load. We have discovered the mass of our irregular object was 49.9 g.

We’ve filled up with water the beaker and the dropper.

We have tried o fill up our graduated cylinder with 30 ml of water. We’ve noticed, when we’ve putted the object inside the cylinder, the water splashed out from the container because the water was too much. So we’ve decided to fill it upwith 20 ml of water and we have observed that it was the right quantity.

We have submerged the irregular object inside the graduated cylinder but at the first attempt, the water splashed out from it. We’ve tried it three times because the water kept to splash out. So we’ve taken the cylinder almost horizontally and we have submerged our irregular object slowly.

We have noticed that the water level was increased by 6 ml.

We have calculated the mean of the results of each group, but we haven’t counted the result of the group that used the elastic because it has absorbed 1 ml and more (because in addition to 1 ml it has compensated the volume of the elastic) so their result was 25 ml.

After we’ve found the mean, that was 26, we have subtracted the measure we’ve found (26) with the water level we have initially (20) With this calculation we have found the volume of our irregular object that was 6 cm 3.

Calculations

 Ratio (between the results of each group): = : 3 = 26  Volume: 26 – 20 = 6 ml = 6 cm 3  Density: d = m/v  d = 49.9 g/6 cm 3 = 8.3 g/cm 3

Discussion

In this experiment we’ve used the method by immersion, because the object was irregular, so we can’t use any formula. It wasn’t difficult because we know the topic yet because we studied it. A group’s made a mistake that was to use an elastic (made of sponge) just because it can absorbs the water, so the result wasn’t accurate enough to be counted with the other.

Conclusion

In conlusion the data collected was supported the hypothesis. We have established that it’s better put less water in the cylinder for avoid that it splash out and so make wrong the esperiment We also learn that it’s better put the object slowly inside the water. We has got some problem with the misuration of the mass (did through the beam balance) because when we put the object on the plate it moved (because it’s cylindrical) so the result is probably not completely correct.