When heated, each side of a cube increases by 2%. Approximately what percentage does cube volume increase?
Physics · Mixed Chapter
JEE Main Practice

Question

When heated, each side of a cube increases by 2%. Approximately what percentage does cube volume increase?

G1 Physics · Accepted Answer

Step 1: Volume V=ℓ³ and Δℓ/ℓ=0.02. Step 2: Small-change approximation: ΔV/V≈3Δℓ/ℓ=0.06. Step 3: Therefore approximately 6%. Exact increase is (1.02³−1)×100%=6.1208%.