Practice question
Question
A 45kg person stands on two bones, each with area 18cm2. What is the average pressure on the bones? (Take g\=9.8m/s2)
Explanation
Pav = FA, F = mg = 45×9.8 = 441N. Total area A = 2×18×10−4 = 3.6×10−3m2. Pav = 4413.6×10−3 = 1.225×105Pa. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.225 × 10⁵ Pa. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.