A body weighs 245N on Earth’s surface. What is its weight at a depth d\=RE/5? (g\=9.8m/s2)
g(d) = g(1−d/RE). d = RE/5, g(d) = 9.8(1−1/5) = 9.8×4/5 = 7.84m/s2. Mass: m = 245/9.8 = 25kg. Weight: W = 25×7.84 = 196N. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 196 N. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.