Answer to Question #131193 in General Chemistry for Alysha

Question

A certain block is floating in water with 77% of itself submerged. It has length of 4.3 cm, a width of 5.9 cm, and a height of 2.75 cm. What is the mass, in kilograms?

Answer 1

The buoyance force is equal to the weight of the object or the force of gravity, F_B = F_g                  

F_g = V_B*P_B*g (force of gravity or the weight of the object = to volume of the object * density of the object * gravity)

F_B = VS * Pw * g (the buoyant force = the volume of the submerged object * density of water * gravity)

Volume of the object = l*w*h = 4.3 cm * 5.9cm * 2.75cm = 69.7675cm³

77% volume of the submerged object = 77/100 * 69.7576 = 53.7210

Therefore, the weight of the object will be, 53.7210 cm³ * 1000 kg/m³ * 10 m/s² = 0.5372 kg/m/s²

Mass of the object = 0.5372 kg/m/s² divide by 10 m/s²     = 0.053721kg