Physics · Heat and Thermodynamics
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100 W heater is used to melt 50 g of ice at OC. How long should the heater be switched on? (Specific latent heat of fusion of ice is 334 J/g)
- A
28 min
- B
16.7 min
- C
2.8 min
- D
167 min
To melt 50 g of ice at 0°C, we need to supply energy equal to:Q = m × Lf
where Q is the heat energy, m is the mass of ice, and Lf is the specific latent heat of the fusion of ice.
Substituting the given values, we get:
Q = 50 g × 334 J/g
Q = 16700 J
Now, the power of the heater is given as 100 W, which means that it can supply 100 J of energy every second. Therefore, the time required to supply 16700 J of energy is:
t = Q/P
t = 16700 J / 100 W
t = 167 seconds
t= 2.8 min
Mathematically other options are incorrect
This option is incorrect.
This option is incorrect.
This is the correct option as per the calculations
This option is incorrect.
Tagged under Physics · Heat and Thermodynamics · 2021