Answer:
When an organism dies, it is usually destroyed by other forms of life and by weathering processes. On rare occasions some body parts—particularly hard ones such as shells, teeth, or bones—are preserved by being buried in mud or protected in some other way from predators and weather. Eventually, they may become petrified and preserved indefinitely with the rocks in which they are embedded. Methods such as radiometric dating—measuring the amounts of natural radioactive atoms that remain in certain minerals to determine the elapsed time since they were constituted—make it possible to estimate the time period when the rocks, and the fossils associated with them.
Answer:
fundamental frequency in helium = 729.8 Hz
Explanation:
Fundamental frequency of an ope tube/pipe = v/2L
where v is velocity of sound in air = 340 m/s; λ is wave length of wave = 2L ; L is length of the pipe
To find the length of the pipe,
frequency = velocity of sound / 2L
272 = 340 / 2 L
L = 0.625 m
If the pipe is filled with helium at the same temperature, the velocity of sound will change as well as the frequency of note produced since velocity is directly proportional to frequency of sound.
Also, the velocity of sound is inversely proportional to square root of molar mass of gas; v ∝ 1/√m
v₁/v₂ = √m₂/m₁
v₁ = velocity of sound in air, v₂ = velocity of sound in helium, m₁ = molar mass of air, m₂ = molar mass of helium
340 / v = √4 / 28.8
v₂ = 340 / 0. 3727
v₂ = 912.26 m /s
fundamental frequency in helium = v₂ / 2L
fundamental frequency in helium = 912.26 / (2 x 0.625)
fundamental frequency in helium = 729.8 Hz
Answer:
18 is a
19 is c
20 i am not sure
Explanation:
18)nucleus contains protons and neutrons
They are volcanoes
The difference between a quiet and explosive eruption is the silica content. In a quiet eruption, the magma is low in silica, allowing the magma to flow out gently. In an explosive eruption, the magma is high in silica, which causes the magma to be thick and sticky.
Transverse wave:
⇨- the way the wave is moving
⟶- Medium - the material it is traveling through
冖- Wavelength - the distance from crest to crest
C - Crest - the highest point on a wave
T - trough - the lowest part on a wave
↕️ - Amplitude - the distance from rest to crest
ྊ - (tinfoil)Wave
Description:
In the beginning of the wave the wavelength is short and the frequency is high so is the energy.and the amplitude is low *i believe* And after the mark of T shown on the image the wavelength is long and the frequency is low and so is the energy and the amplitude is high *i believe*.Amplitude and wavelength are both measures of distance.
Longitudinal/Compressional Wave:
KEYS:
⟶-medium - the material it is traveling through
⇨-way the wave is moving
冖-wavelength - the distance from crest to crest
R -Rarefaction - the opposite of compression
C-Compression - particles are closest together
