A block of wood (dimensions : 40 cm × 20 cm × 10 cm) is kept on a tabletop in three different positions : (a) with its side of dimensions 20 cm × 10 cm; (b) with its side of dimensions 10 cm × 40 cm; and (c) with its side of dimensions 40 cm × 20 cm. The pressure exerted by the wooden block on the tabletop in these positions is represented by PA, PB and Pc, respectively. The pressure follows the trend

The pressure exerted by an object on a surface is defined as the force acting per unit area (Pressure = Force / Area). In this scenario, the force is the weight of the wooden block, which remains constant regardless of its orientation on the tabletop.

The contact areas for the three positions are calculated as follows:

• Position (a): Area AA = 20 cm × 10 cm = 200 cm²
• Position (b): Area AB = 10 cm × 40 cm = 400 cm²
• Position (c): Area AC = 40 cm × 20 cm = 800 cm²

Since pressure is inversely proportional to the area of contact (P ∝ 1/A) for a constant force, the position with the smallest contact area exerts the highest pressure. Because Area AA < Area AB < Area AC, the resulting pressures follow the trend PA > PB > PC, making Option A correct.