To determine the energy needed to increase the temperature of a kilogram of water by 5 degrees Celsius, we can use the formula:
Q = mcΔT
Where:
- Q = Heat energy (in joules)
- m = mass of the water (in kg)
- c = specific heat capacity of water (in J/kg·K)
- ΔT = change in temperature (in degrees Celsius)
In this case, we have:
- m = 1 kg
- c = 4184 J/kg·K
- ΔT = 5 °C
Now, plugging in the values:
Q = 1 kg × 4184 J/kg·K × 5 °C
Calculating this gives:
Q = 20920 J
Thus, the energy needed to increase the temperature of a kilogram of water by 5 degrees Celsius is 20920 joules.