A rectangular concrete anchor block is used in deep-water pressure tests.
Explain why the forces on the block resting at the bottom of the container cause the block to remain stationary.
When the block is at the bottom of a shallow testing pool, the top surface of the block is 4.50 m below the surface of the liquid. The force acting on the top surface of the block due to the weight of the liquid is 6350 N. The gravitational field strength is g=9.8 N/kgg = 9.8\text{ N/kg}g=9.8 N/kg. Calculate the density of the liquid in this pool. Give your answer to 3 significant figures.
The block is then lowered into a very deep geological test shaft filled with a different industrial fluid. When the block is at a depth of 5.00 m in this deep shaft, the force due to the pressure of the fluid on its top surface is 4980 N.
Determine the force due to the weight of the fluid on the top surface of the block when it is at the bottom of this shaft at a depth of 42.5 m. Give your answer to 3 significant figures.