100 W heater is switched on for 5 minutes to melt ice. What is the mass of ice that melts at 0oC? ( The specific latent heat of fusion of ice is 334 J/g).
Correct answer: A. 90 g
- A. 90 g
- B. 90 kg
- C. 1.5 kg
- D. 1.5 g
Explanation
To calculate the mass of ice that melts, we can use the formula:Q = m * Lwhere:Q = heat energy absorbed or released during a phase change (in joules)m = mass of the substance that melts (in grams)L = specific latent heat of fusion (in J/g)Given information:Power of the heater (P) = 100 WTime (t) = 5 minutes = 5 * 60 seconds = 300 secondsSpecific latent heat of fusion of ice (L) = 334 J/gFirst, we need to calculate the total energy supplied by the heater:Energy (Q) = Power (P) * Time (t)Energy (Q) = 100 W * 300 secondsEnergy (Q) = 30,000 joulesNow, we can calculate the mass of ice that melts:m = Q / Lm = 30,000 joules / 334 J/gm ≈ 90 gSo, approximately 90 g of ice will melt when the 100 W heater is switched on for 5 minutes.
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