How Long Does It Take to Heat Ice from -15C to 55C Water?

AI Thread Summary
To determine how long it takes to heat ice from -15°C to 55°C using a 40-watt hot plate, the heat required (Q) must first be calculated. The formula involves the specific heat capacities and phase changes of ice and water. Once Q is known, the relationship between power, energy, and time can be applied using the equation P = Q/T, where P is power. By rearranging this equation to solve for time (T), the total heating duration can be found. Understanding these concepts is crucial for accurately calculating the heating time.
TwoBelt
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Homework Statement


I just solved how much heat is needs to make a -15C ice to 55C water but i don't know how to find how long it takes.

How long will it take to reach 55C?

Homework Equations





The Attempt at a Solution


Not even sure where to begin
 
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Are you given a heater of some wattage is being used to provide the heat?
 
yes its a 40 watt hot plate i didnt see that before. So would you do 40w=Q/T(variable)?
 
TwoBelt said:
yes its a 40 watt hot plate i didnt see that before. So would you do 40w=Q/T(variable)?

Yes, remember that Power = Rate of transfer of energy / time, so you are correct.
 
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