Answer:
D. Frequency
Explanation:
The energy of an electromagnetic wave is proportional to frequency, mathematically it is expressed as;
E ∝ f
E = hf
where;
h is Planck's constant = 6.626 x 10⁻³⁴ Js
The equation above can also be expanded to;
where;
c is speed of light = 3 x 10⁸ m/s
λ is the wavelength of the electromagnetic wave
Since the speed of light is constant, we can conclude that the energy of the electromagnetic wave is directly proportional to its frequency and inversely proportional to its wavelength.
Therefore, the correct option for direct proportionality is FREQUENCY
Answer:
C. The facial feedback theory
Explanation:
The facial feedback theory as postulated by William James and connects back to the famous Charles Darwin talks about how facial expressions stimulate our emotional state of being. Based on this theory, the emotional experiences we have are determined by the looks on our faces.
According to the question, smiling at an event makes you enjoy it is an example of what the The facial feedback theory is explaining. Furthermore, smiling, which is a facial expression causes or stimulates an emotional state of enjoyment in that event.
A reasonable estimate for the height of the walls in an ordinary American home is 2.5m.
<h3>What is wall estimation?</h3>
Building gauge is of two sorts one is known as Rough Cost Estimate. This gauge won't depict the specific expense of the structure, however it can provide you with the rough expense worth of the structure that will help adequately in overseeing cash for the structure. Harsh Cost Estimate is directed in various ways for various sort of structures. The rough complete wall length is found in running meters in this framework and this all out length accumulated by the rate per running meter of the wall gives an actually solid cost. Assessment hypothesis is a part of insights that arrangements with assessing the upsides of boundaries in light of estimated experimental information that has an irregular part. The boundaries depict a fundamental actual setting so that their worth influences the circulation of the deliberate information.
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Answer: 529.9 Hz
Explanation:
Here we need to use the Doppler equation, so we have:
f' = f*(v + v0)/(v - vs)
Here, f is the frequency = 500Hz
v is the velocity of the wave, = 334m/s
v0 is the velocity of the observer = 20m/s
vs is the velocity of the source = 0m/s
Then we have:
f' = 500Hz*(334m/s + 20m/s)/(334m/s) = 529.9 Hz
