Fossil fuels . . . coal, oil, natural gas
Among primitive cultures, wood is an important source.
Answer:
Distance
Explanation:
distance is in vertical axis,or y-axis and time is on the horizontal axis,or x-axis.
Since the frequency of sound in a medium is constant, therefore, the concert-goers would hear the low notes and high notes at the same time.
<h3>What is a dispersive medium?</h3>
A dispersive medium is a medium which spreads out or disperses a substance passing through it.
Since CO2 is a dispersive medium, it means sound waves passing through it would be dispersed based on wavelength.
The note of a sound depends on its frequency, the higher the frequency, the higher the note.
Frequency of sound is constant, therefore, the concert-goers would hear the low notes and high notes at the same time.
Learn more about dispersion of sound at: brainly.com/question/781734
Question:
A 63.0 kg sprinter starts a race with an acceleration of 4.20m/s square. What is the net external force on him? If the sprinter from the previous problem accelerates at that rate for 20m, and then maintains that velocity for the remainder for the 100-m dash, what will be his time for the race?
Answer:
Time for the race will be t = 9.26 s
Explanation:
Given data:
As the sprinter starts the race so initial velocity = v₁ = 0
Distance = s₁ = 20 m
Acceleration = a = 4.20 ms⁻²
Distance = s₂ = 100 m
We first need to find the final velocity (v₂) of sprinter at the end of the first 20 meters.
Using 3rd equation of motion
(v₂)² - (v₁)² = 2as₁ = 2(4.2)(20)
v₂ = 12.96 ms⁻¹
Time for 20 m distance = t₁ = (v₂ - v ₁)/a
t₁ = 12.96/4.2 = 3.09 s
He ran the rest of the race at this velocity (12.96 m/s). Since has had already covered 20 meters, he has to cover 80 meters more to complete the 100 meter dash. So the time required to cover the 80 meters will be
Time for 100 m distance = t₂ = s₂/v₂
t₂ = 80/12.96 = 6.17 s
Total time = T = t₁ + t₂ = 3.09 + 6.17 = 9.26 s
T = 9.26 s
Here is the full question:
The rotational inertia I of any given body of mass M about any given axis is equal to the rotational inertia of an equivalent hoop about that axis, if the hoop has the same mass M and a radius k given by:
The radius k of the equivalent hoop is called the radius of gyration of the given body. Using this formula, find the radius of gyration of (a) a cylinder of radius 1.20 m, (b) a thin spherical shell of radius 1.20 m, and (c) a solid sphere of radius 1.20 m, all rotating about their central axes.
Answer:
a) 0.85 m
b) 0.98 m
c) 0.76 m
Explanation:
Given that: the radius of gyration
So, moment of rotational inertia (I) of a cylinder about it axis = 
k = 0.8455 m
k ≅ 0.85 m
For the spherical shell of radius
(I) = 
k = 0.9797 m
k ≅ 0.98 m
For the solid sphere of radius
(I) = 
k = 0.7560
k ≅ 0.76 m
