Question #185b5

1 Answer
Jan 30, 2015

Well, the formula you've used for density is wrong. Density equals mass divided by volume, not multiplied like you show in the question.

#rho = m/V#

I assume the three dimensions of the box (it's acutally a reactangular prism, to be precise) are expressed in mm. Indeed the volume of this box is

#V = A * B * C = "81 mm" * "57 mm" * "43 mm"#

#V = "198531 mm"^3#

This means that the mass of the part is

#m = rho * V = 0.0079# #"g"/"mm"^3 * "198531 mm"^3 = "1568.4 g"#

If you want the answer rounded to two sig figs, the mass is

#m = "1600 g"#, or #m = "1.6 kg"#