A physical quantity Q is found to depend on quantities a, b, c by the relation Q = a⁴b³/c². The percentage error in a, b and c are 3%, 4% and 5% respectively. Then, the percentage error in Q is :
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A physical quantity Q is found to depend on quantities a, b, c by the relation Q = a⁴b³/c². The percentage error in a, b and c are 3%, 4% and 5% respectively. Then, the percentage error in Q is :

G1 Physics · Accepted Answer

Q = a⁴b³/c² ΔQ/Q = 4Δa/a + 3Δb/b + 2Δc/c (ΔQ/Q) × 100 = 4[(Δa/a) × 100] + 3[(Δb/b) × 100] + 2[(Δc/c) × 100] % error in Q = 4 × 3% + 3 × 4% + 2 × 5% = 12% + 12% + 10% = 34%