Answer:
20 J/g
Explanation:
In this question, we are required to determine the latent heat of vaporization
- To answer the question, we need to ask ourselves the questions:
What is latent heat of vaporization?
- It is the amount of heat required to change a substance from its liquid state to gaseous state without change in temperature.
- It is the amount of heat absorbed by a substance as it boils.
How do we calculate the latent heat of vaporization?
- Latent heat is calculated by dividing the amount of heat absorbed by the mass of the substance.
In this case;
- Mass of the substance = 20 g
- Heat absorbed as the substance boils is 400 J (1000 J - 600 J)
Thus,
Latent heat of vaporization = Quantity of Heat ÷ Mass
= 400 Joules ÷ 20 g
= 20 J/g
Thus, the latent heat of vaporization is 20 J/g
Answer:
F = 768 N
Explanation:
It is given that,
Speed of the elevator, v = 3.2 m/s
Grain drops into the car at the rate of 240 kg/min, 
We need to find the magnitude of force needed to keep the car moving constant speed. The relation between the momentum and the force is given by :
Since, the speed is constant,
F = 768 N
So, the magnitude of force need to keep the car is 768 N. Hence, this is the required solution.
