- #1
alexandria
- 169
- 2
Homework Statement
Homework Equations
relevant equations listed with each question
The Attempt at a Solution
a)
to solve for the power output of the heater, i used the following equation: Power = Energy/time
i already know that Energy = Quantity
so based on this, i can solve for Q = mass(ice) x specific heat capacity (ice) x change in temperature (ice)
Q = (0.25 kg) x (2100 J/kg.C) x (0 degrees - (-30 degrees) = 15 750 J
Using Q, i substituted it into the equation to solve for power
P = 15 750 J / 150 s (150 s is the time shown on the graph)
P = 105 Watts
is this correct?
i need to know if this is right so i can use the power to do the next questions.
this is my second attempt to part a). the only difference is the change in temperature, instead of using 0 degrees, i used -10 degrees based on the graph above:
Q = (0.25 kg) x (2100 J/kg.C) x (-30 degrees - (-10 degrees) = 10 500 J
Using Q, i substituted it into the equation to solve for power
P = 10 500 J / 150 s
P = 70 Watts
i don't know if my attempts are correct, if anyone can clarify what I am supposed to do here, that would be greatly appreciated. Once i figure out what to do here, i can answer the next questions and post them on this forum for clarification as well.