Answer:
Initially, the ballast tanks are filled with water. The weight of the submarine is equal to the upthrust of the water at the position of the submarine under water. When high pressure air is released into the ballast tanks displacing the water, the weight of the submarine becomes less than the upthrust of the water thus the net force is is upwards and it forces the sub to resurface. This is according to the Archimedes principle which states that a a body partially or wholly immersed in water displaces its own weight of the fluid in which it is immersed.
Ultraviolet Rays ( UV rays) can harm humans because they can cause sunburn, and skin cance if you stay out in the sun for too long.
Answer:
3 × 10⁴ kJ
Explanation:
Step 1: Write the balanced thermochemical equation
C₃H₈(g) + 5 O₂(g) ⟶ 3 CO₂(g) + 4 H₂O(g) ΔH = -2220 kJ
Step 2: Calculate the moles corresponding to 865.9 g of H₂O
The molar mass of H₂O is 18.02 g/mol.
865.9 g × 1 mol/18.02 g = 48.05 mol
Step 3: Calculate the heat produced when 48.05 moles of H₂O are produced
According to the thermochemical equation, 2220 kJ of heat are evolved when 4 moles of H₂O are produced.
48.05 mol × 2220 kJ/4 mol = 2.667 × 10⁴ kJ ≈ 3 × 10⁴ kJ
Answer:
The length of the fence is 22.5ft and the width of the fence is 7.5ft.
Explanation:
To solve this problem we will turn this question into an equation.
The equation for the perimeter of a rectangle is 2l + 2w = perimeter.
In the question we were given the perimeter so we can go ahead and plug this in.
2l + 2w = 60
In the question we are also told that the fence is 3 times as long as it is wide. This means that 1l = 3w. We can now subsitute l for 3w so that we only have one variable.
2(3w) + 2w = 60
Now we can simply use algebra to solve for w.
6w + 2w = 60
8w = 60
w = 7.5
Now that we know the value of w we can find the value of l since we know 1l = 3w.
l = 3w
l = 3(7.5)
l = 22.5
The length of the fence is 22.5ft and the width of the fence is 7.5ft.