Answer:
Cp = 4756 [J/kg*°C]
Explanation:
In order to calculate the specific heat of water, we must use the equation of energy for heat or heat transfer equation.
Q = m*Cp*(T_f - T_i)/t
where:
Q = heat transfer = 2.6 [kW] = 2600[W]
m = mass of the water = 0.8 [kg]
Cp = specific heat of water [J/kg*°C]
T_f = final temperature of the water = 100 [°C]
T_i = initial temperature of the water = 18 [°C]
t = time = 120 [s]
Now clearing the Cp, we have:
Cp = Q*t/(m*(T_f - T_i))
Now replacing
Cp = (2600*120)/(0.8*(100-18))
Cp = 4756 [J/kg*°C]
Conservation in this case means that it doesn't change. Momentum isn't created or destroyed, but it remains constant.
Answer:
1 ) Warm air
2) Cold air
3) Cold water
4) Steel
5) Hot molten
Explanation:
In order to solve this problem, we have to warn that the sound propagates more easily in denser media, in this way we have to identify the densities of the different materials.
Density cold air = 1.2 [kg/m^3]
Density warm air = 1.01 [kg/m^3]
Density cold water = 1000 [kg/m^3]
Density steel = 7500 [kg/m^3]
Density hot molten = 14100 [kg/m^3]
Therefore in order from the slowest to the fastest:
1 ) Warm air
2) Cold air
3) Cold water
4) Steel
5) Hot molten
