What is the change in entropy of helium gas with total mass 0.135 kg at the normal boiling point of helium when it all condenses isothermally to liquid helium? Assume that the normal boiling point of helium is 4.216 K and the heat of vaporization of helium is 2.09×104 J/kg .

-669.2 J/k

Explanation:

We are given that

Mass=m=0.135 kg

Normal boiling point,B.P=4.216 K

Heat f of vaporization=

We have to find the change in entropy of helium gas.

Using the formula then, we get

Hence, the change in entropy of helium gas=-669.2 J/k

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2