The weight of a block of granite 1 ft × 2 ft × 4 ft is 1320 lb. If it stands on a small face (1 ft × 2 ft), what is the pressure on the bottom face? A) 1.15 lb/in² B) 2.29 lb/in² C) 4.58 lb/in² D) 9.17 lb/in²

Question

Quizplus · Accepted Answer

The pressure on the bottom face is equal to the weight of the block divided by the area of the bottom face. The area of the bottom face is 1 ft × 2 ft = 2 sq ft.

Pressure = Weight / Area = 1320 lb / 2 sq ft = 660 lb/sq ft

Converting to lb/in²: 
1 sq ft = 144 sq in 
660 lb/sq ft = 660 lb / 144 sq in ≈ 4.58 lb/in²

Therefore, the pressure on the bottom face is 4.58 lb/in², which is answer choice C.

The Weight of a Block of Granite 1 Ft ×