Answer:
17,890 J
Explanation:
The amount of heat released by a gaseous substance when it condenses is given by the formula

where
n is the number of moles of the substance
is the latent heat of vaporization
The formula can be applied if the substance is at its vaporization temperature.
In this problem, we have:
n = 0.440 mol is the number of moles of steam
is the latent heat of vaporization of water
And the steam is already at 100C, so we can apply the formula:

(a) We know that work is the product of Force and Distance so: (in this
case Distance is negative since going down so –d)
work = force * distance
work = M * (g - g/4) * -d
work = -3Mgd/4 <span>
(b) The work by the weight of the block is simply:</span>
work = Mgd <span>
(c) The kinetic energy is simply equivalent to the
net work, therefore:</span>
KE = net work
KE = Mgd/4 <span>
(d) The velocity is:</span>
v = √(2*KE/M)
Plugging in the value of KE from c:
v = √(2*Mgd / 4M)
<span>v = √(gd / 2) </span>