(i) A sealed lightweight plastic cube of sides

0.75m

is submerged under water, as shown in Figure Q3a. Find the net hydrostatic forces acting on the cube.\ [8]\ (ii) If the cube is lowered further in the water, what effect does this have on the hydrostatic forces?\ [1]\ (iii) If the cube must be maintained in the location shown in Figure Q3a using a rope tied to a concrete block, what volume of concrete is required?\ [1]\ (Note: acceleration due to gravity

g=9.81(m^(2))/(s)

; water density

\\\ ho =1000k(g)/(m^(3))

; concrete density

\\\ ho =2400k(g)/(m^(3))

)\ Figure Q3a

(i) A sealed lightweight plastic cube of sides 0.75m is submerged under water, as shown in Figure Q3a. Find the net hydrostatic forces acting on the cube. [8] (ii) If the cube is lowered further in the water, what effect does this have on the hydrostatic forces? [1] (iii) If the cube must be maintained in the location shown in Figure Q3a using a rope tied to a concrete block, what volume of concrete is required? [1] (Note: acceleration due to gravity g=9.81m2/s; water density =1000kg/m3; concrete density =2400kg/m3 ) Figure Q3a