A metal has a specific heat capacity of 500J/(kg°C). A block of this metal has a mass of
1.20kg and is provided with thermal energy by a heater for 5.00 minutes. The temperature of the
block increases from 40.0°C to 90.0°C without a phase change.
What is the power of the heater?
[Assume that no thermal energy is lost to or gained from the surroundings and that the metal is
at a uniform temperature at all times.]
180W
10800W
100W
80W
6000W
Hi!
energy = specific heat capacity x mass x temperature change
= 500 x 1.2 x (90-40)
= 30 000 J
power = energy / time
= 30 000 / 5 x 60
= 100 W
Hope this helps!
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