Answer:
The science of thermodynamics deals with the fundamental laws that guide how physical processes occur in relation with the energy transfer. When a system or process changes from one state of equilibrium to another, thermodynamics is interested with the amount of heat transfer during the process. On the other hand, the science of heat transfer is simply about the rate of heat and temperature distribution inside a system at a particular point in time.
Explanation:
Assuming that the densities of the gases are:
density of air, ρ1 = 1.29 kg / m^3
density of helium, ρ2 = 0.179 kg / m^3
Since buoyant force and weight are two forces that are in
opposite direction (buoyant force is up while weight is down), therefore equate
the two:
buoyant force = weight
m g = (800 + m1) g
where m is the mass of buoyancy, g is gravity and m1 is
the maximum mass of the cargo
m = 800 + m1
We know that mass is also expressed as:
m = ρ V
where ρ is density of gas and V is volume of the sphere
Since there are two interacting gases here, therefore m
is:
m = (ρ1 – ρ2) V
Therefore:
(ρ1 – ρ2) V = 800 + m1
(1.29 – 0.179) (4π/3) (8.35m)^3 = 800 + m1
2709.33 = 800 + m1
m1 = 1,909.33 kg
Answer:
- 1100 J heat flows out
Explanation:
dW = - 1600 J (as work is done on the gas)
dU = 500 J
dQ = ?
According to the first law of thermodynamics
dQ = dU + dW
dQ = 500 - 1600
dQ = - 1100 J
As heat is negative so it flows out.
