A device that converts light energy into electrical energy is MCQ with Answer and Explanation

Explanation:
Water's high specific heat (4186 J/kg·K) means it absorbs/releases large heat with small temperature change. This stabilizes temperatures: in engines, water coolant absorbs heat without large ΔT; in organisms, it buffers against temperature fluctuations. Memory tip: 'High specific heat = thermal buffer; water moderates climate and body temperature'. This application question tests understanding of material properties, frequently appearing in competitive exams. Always link physical properties to real-world uses; competitive exams emphasize practical implications of physics concepts.

Explanation:
The acceleration due to gravity is given by g = GM/R². For a small change, taking the derivative or using error approximation: Δg/g = -2(ΔR/R). If R shrinks by 1% (ΔR/R = -1%), then Δg/g = -2(-1%) = +2%. Therefore, the value of 'g' will increase by approximately 2%.

Explanation:
Volume V = (4/3)πr³. Fractional error ΔV/V = 3 Δr/r. Percentage error = 3 × 2% = 6%. Important for error analysis in competitive exams.