Answer:
the volume of the sound will quarter
Explanation:
As you move far away from the source, the loudness of sound decreases. This is because as the distance from the source increases, the area it covers also increases thereby spreading the energy over a great area leading to lesser loudness and intensity.
As a result of this, sound intensity follows an inverse square law:
I ∝ 1/d²; where I is the intensity and d is the distance from source.
Therefore If a speaker is moved from 2 feet away to 4 feet away (increment of 2 feet), the volume of the sound would quarter (1/2² = 1/4)
Answer:
The term Big Bang defines that the Universe has expanded from the ancient hot and thick primary situation at some fixed time in the past.
Big Bang theory refers to the origin of the Universe. In the beginning, universe is very heavy and small hot ball of matter. It was a point no bigger than the head of a pin when all the things squished with each other and universe is expanded with huge explosion of energy. Due to expansion, it is cooled and results in the formation of Stars and galaxies. After sometime, atoms formed like helium and hydrogen.
Thus, statement (1), (3) and (4) is correct whereas statement (2) and (5) is incorrect. the right answer is - (It expanded slowly), (Stars and galaxies formed,) (Atoms such as hydrogen and helium formed.)
Explanation:
The combustion of ammonia in presence of excess oxygen yields NO2 and H2O.
The molar mass of ammonia is 17.02 g/mol
Therefore, moles of ammonia in 43.9 g
= 43.9 /17.02
= 2.579 moles
From the equation the mole ratio of ammonia to nitrogen iv oxide is 4:4
The molar mass of NO2 is 46 g/mol
The number of moles of NO2 is the same as that of ammonia since they have equal ratio,
= 2.579 moles
Therefore, mass of NO2
= 2.579 moles ×46
= 118.634 g
≈ 119 g
