Density Block Lab

           My partner and I are given the task of trying to determine the mass of a plastic block using its density and volume. We had to have a percent error of less than 5%. The only tool available for us is a ruler, and we were given the density, 2.70 g/cm^3.
           We started off by determining to use the formula of density=mass/volume to find the mass. First, we needed to find the volume so we used the ruler to measure the length, height, and width of the block, where we got 2.50 cm x 2.50 cm x 2.50 cm. We multiplied these measures together to get the volume, using the formula of volume = length x height x width, where we got 15.625 cm^3. Plugging these values into the formula of density=mass/volume, we got 2.70 g/cm^3 = mass / 15.625 cm^3, and we solved the equation to get 42.1875 grams. Using the properties of significant figures, 42.1875 was simplified to 42.2. Thus, our calculated mass was 42.2 grams.
           We found out the actual mass of the block was 43.9 grams, so we were off by 1.7 grams. Using the %of error formula, %error = (actual - experimental)/(actual) x 100%, we found out we had an error of 3.87%. A possible error that might have occured to cause our calculated mass to differ from the actual mass is not measuring the length, width, and height precise enough. During the experiment, my partner and I each measured the length, height, and width of the block and our answers slightly differed. We later compromised, but this event displays how our measures were not completely accurate. In future lab investigations, we should measure the lengths more than once in order to ensure our data accuracy.
Picture of some of our work

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