A cube of aluminum with sides 30 cm rests on the floorThe specific gravity of aluminum is 2.7a) Calculate the weight of the cube.b) Calculate the pressure exerted on the floor by the cube.The answer are 714N and 7930 Pa i'm just not sure how to get the answers especially to part a.
Specific gravity of 2.7 means that one litre of aluminium has a mass of 2.7kgThe cube has volume of 27 litres (because 1litre1dm^3, and 1dm10cm) and therefore a mass of 27x2.7 72.9kgAssuming g9.8, the weight is given by Wmg as 714.42NPressure is force per unit areaThe area of the cube in contact with ground is 0.3x0.30.09m^2Therefore the pressure the cube exerts on the ground is 714/0.097938Pa(slightly different answer, probably due to rounding errors or different value for g)
