a square based brass plate is 2mm high and has a mass of 1.05 the density of the brass is 8.4g/cubic cm.calculate the length of the plate in cm
If the plate has length and width x cm, then the volume is 0.2x^2 cm^3,
density is mass/volume, so we have
8.4 g/cm^3 = 1.05g / (0.2x^2 cm^3)
or,
8.4 = 5.25/x^2
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