Answer:
The entropy change is 45.2 kJ/K.
Explanation:
mass of water at 100 C = 2 kg
Latent heat of vaporization, L = 2260 kJ/kg
Heat is
H = m L
H = 2 x 2260 = 4520 kJ
Entropy is given by
S = H/T = 4520/100 = 45.2 kJ/K
Answer:
Work done is 50.4J.
Explanation:
The work
done by the student in lifting the book 1.2 meters vertically is


When the student begins to walk horizontally, the net force on the book is zero <em>(gravity is pulling it down, the student is lifting it up)</em>. Thus, although the student is displacing the book horizontally, but because no force is exerted on it, the work done is zero.
The net force is zero due to the direction.
We need to know about force resultant to solve this problem. The force resultant is the total net force applied to the object according to the direction. It can be written as
R = F1 + F2 + ... + Fn
where R is force resultant (net force)
From the question above, we know that
F1 = F2 = F N
Because the direction is the same, the force will be minus each other.
R = F1 - F2
R = F - F
R = 0 N
Hence, the net force is 0 N
Find more on net force at: brainly.com/question/14361879
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