<span>The amount of dissolved oxygen in water may decrease
because of the increase in organic matter in the water. <span>Aquatic organisms breathe and use oxygen. Large amounts of
oxygen are consumed by the decomposition of bacteria (when there are large
amounts of dead matter to decompose, there will be a significant number of
bacteria). Examples: dead organic matter (algae), wastewater, garden waste,
oils and fats, all this results in a decrease in dissolved oxygen in the water.</span></span>
Answer:
Chain reaction is possible by neutron
Explanation:
Nuclear reaction is mainly two types,
⇒ Nuclear Fission : heavy atom split into two light atom.
Ex. Uranium, thorium
⇒ Nuclear fusion : lighter atom combine together
Ex. Hydrogen to helium
In fusion reaction the large amount of energy is produced as compare to fission reaction.
Sun gets brighter by fusion reaction.
In case of uranium fission reaction is possible by colliding neutron.
Answer:
259.274 kW
Explanation:
Given:
Area of the lava, A = 1.00 m²
Temperature of the surrounding, T₁ = 30.0° C = 303 k
Temperature of the lava, T₂ = 1190° C = 1463 K
emissivity, e = 1
Now,
from the Stefan-Boltzmann law of radiation the rate of heat loss is given as,
u = σeA(T₂⁴ - T₁⁴)
where,
u = rate of heat loss
σ = Stefan-Boltzmann constant = 5.67 × 10⁻⁸ W/m²∙K⁴
on substituting the respective values, we get
u = 5.67 × 10⁻⁸ × 1 × 1 × (1463⁴ - 303⁴)
or
u = 259274.957 W
or
u = 259.274 kW
Answer:
V₁ = √ (gy / 3)
Explanation:
For this exercise we will use the concepts of mechanical energy, for which we define energy n the initial point and the point of average height and / 2
Starting point
Em₀ = U₁ + U₂
Em₀ = m₁ g y₁ + m₂ g y₂
Let's place the reference system at the point where the mass m1 is
y₁ = 0
y₂ = y
Em₀ = m₂ g y = 2 m₁ g y
End point, at height yf = y / 2
= K₁ + U₁ + K₂ + U₂
= ½ m₁ v₁² + ½ m₂ v₂² + m₁ g 
+ m₂ g
Since the masses are joined by a rope, they must have the same speed
= ½ (m₁ + m₂) v₁² + (m₁ + m₂) g
= ½ (m₁ + 2m₁) v₁² + (m₁ + 2m₁) g
How energy is conserved
Em₀ =
2 m₁ g y = ½ (m₁ + 2m₁) v₁² + (m₁ + 2m₁) g
2 m₁ g y = ½ (3m₁) v₁² + (3m₁) g y / 2
3/2 v₁² = 2 g y -3/2 g y
3/2 v₁² = ½ g y
V₁ = √ (gy / 3)
Answer:
a) W=85.225 kW
b) 
Explanation:
First, consider the energy balance for the compressor: The energy that enters to the system (W and enthalpy of the feed flow) is equal to the energy that goes out from it (Heat Q and enthalpy of the exit flow):
Consider the enthalpy data from van Wylen 6th edition, Table B.2.2. According to that, 
, 
So, the power input to the compressor is:
b) The differential entropy change dS for a reversible heat transfer dQ at a temperature T is:
This equation can be integrated if the heat transfer surface temperature remains constant, which is the case, giving as a result:
