A solid cylinder has an area of 10cm2 and a height of 1.0 m. The cylinder is composed of two different materials with mass densities of 2000 kg/m3 and 1500 kg/m3. If each of the two materials occupies an equal volume, what is the mass of the cylinder?

Question 3 options:
A) 3.5kg

B) 2.5kg

C) 25kg

D) 1.75kg

1 answer

1m = 100cm.

V = 10cm^2 * 100cm = 1000cm^3.
1000cm^3 = 1*10^-3 m^3.

1*10^-3m^3/2 = 0.5*10^-3m^3 = 5*10^-4.

Mass = (2000kg/m^3)*5*10^-4m^3 +
(1500kg/m^3)*5*10^-4 = 3500*5*10^-4 =
1.75kg.