Nitrogen is the most abundant of the gases present in the atmosphere. 78 percent of the atmospheric air comprises of nitrogen, oxygen makes up for 21 percent and all other gases make up for the remaining one percent. Oxygen is a highly flammable gas and in the absence of nitrogen it would not have been possible to utilize this atmospheric oxygen, hence the presence of nitrogen reduces its flammability and also neutralizes the toxicity of other gases.
The correct answer is A. Acid rain forms from human activities and lowers the pH of rainwater below 7
Explanation:
The term "acid rain" is used to refer to rainwater with a low pH or a high acidity, this includes rainwater with a pH below 7 (solutions with a pH under 7 are acidic). In terms of formation, acid rain is mainly the result of human activities such as factories or cars that release pollutants into the atmosphere including nitric and sulfuric acids and these alter the natural pH of rain and makes it more acidic. Additionally, acid rain has negative consequences such as the death of fishes and other organisms in lakes, rivers, etc. because the acidity is toxic to many organisms. Thus, acid rain is the result of human activities and it lowers the pH of rain (Option A).
Answer:
Spaceship speed is 36000 km/h
So, in 1 hour spaceship travel 36000 km
Or we can say that in 60×60 second spaceship travel 36000 km
Therefore in 1 sec spaceship travel
=
= 10 km/s
If the length of the ruler is 50 cm, the center of gravity cannot be greater than 25 cm.
The given parameters:
- Weight of the ruler = 1 N
<h3>What is center of gravity (CG)?</h3>
- Center of gravity is the point at which the weight of an object is concentrated.
Let the length of the ruler = L
The center of the gravity of the ruler is calculated as follows;
Thus, if the length of the ruler is 50 cm, the center of gravity cannot be greater than 25 cm. This may change if the length of the ruler changes because the center of gravity of uniform ruler depends on the length of the ruler.
Learn more about center of gravity here: brainly.com/question/6765179
Answer:
The velocity is 18.68m/s
Explanation:
Bernoulli's equation is applicable for stream line flow of a fluid. The flow must be steady and uniform flow. The Bernoulli's equation between inlet and outlet is written as:
P1/pg + V1/2g + Z1 = P2/pg + V2^2 + Z2
Where V1 and V2 are velocity of fluid at point 1 and 2b. The diameter of the tank too will be larger than that of the nozzle. Hence the velocity at point 1 will be 0.V1= 0
Substituting the values in to the equation
250 ×10^3/1000g + 0/g + 2.5 = 100×10^3/1000g + V2^2/2g + 0
250 + 2.5g = 100 + V2^2/2
250 + (2.5 × 9.8) = 100 V2^2/2
250 + 23.525- 100 = V2^2/2
174.525 = V2^2/2
Cross multiply
174.525 × 2 = V2^2
V2 = 349.05
V2 = Sqrt(349.05)
V2 = 18.68m/s
