Question

A rectangular bar of platinum has a width of 5 centimeters, a height of 8 centimeters, and an unknown length. You measure the platinum bar and it is exactly 1 kilogram. Find the length of the bar if you know its density is 21.4 g/cm3
21.4

g/cm
3
. Round your answer to the nearest hundredth.(1 point)
cm

Answer 1

Mass = density × volume, so volume = mass/density = 1000 g / 21.4 g/cm³ = 1000/21.4 cm³.

Cross-sectional area = 5 cm × 8 cm = 40 cm², so length = volume/area = (1000/21.4) / 40 = 1000 / 856 ≈ 1.1682243 cm.

Rounded to the nearest hundredth: 1.17 cm.