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3 years ago

Which of the following is a difference between electromagnetic waves and sound waves?

Physics

1 answer:

Paul [167]3 years ago

7 0

Answer:

Explanation:

A is wrong as otherwise the ocean would be black as light could not pass through it to create images.

B is wrong. This is a weird one as the electromagnetic spectrum attached below shows that radio waves have the least amount of energy vs gamma which has the highest and you can't really compare this to sound waves.

C just straight up false.

D is correct, no way to remember this, just learn it. a couple of facts about transverse waves of google. Electromagnetic waves are a type of transverse waves. These waves do not require a medium to travel. As the name of the waves imply, these waves show electrical and magnetic properties. No any charge occur in the waves. Electromagnetic waves work by the laws of reflection and refraction. They travel as straight lines in a vacuum at a speed of 3 x 10 8 ms -1.

Extra info:

As gamma waves have the highest energy it means that the waves are closer together (the wavelength is smaller) and they create more heat. Also gamma waves go through everything, X-ray only through skin and bounces of dense things like bones, which creates images. These eventually weaken more and more until radio waves do not pass through anything and just bounces around and everywhere which allows you to gain more coverage on a radio then on a cell phone.

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According to ____, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on other variable

irakobra [83]

Answer:

Signal detection theory

Explanation:

Signal detection theory states that stimulus ca be detected according to its intensity and a person's psychological and/or physical state. This means that we can notice things according to how strong they are but also, a person's characteristics like experience and physiological state like fatigue can affect the ability to detect them.

Because of this, the answer is that according to signal detection theory, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on other variables such as the level of noise in the system and your expectations.

8 0

3 years ago

Help Please!!!!!!!!!!!!!!!!!!

julia-pushkina [17]

The answer is 59.4 degrees.

4 0

3 years ago

A flywheel turns through 40 rev as it slows from an angular speed of 1.5 rad/s to a stop.

Lynna [10]

Answer:

-0.0047 rad/s²

335.103 seconds

99.18 seconds

Explanation:

$\omega_f$ = Final angular velocity

$\omega_i$ = Initial angular velocity = 1.5 ra/s

$\alpha$ = Angular acceleration

$\theta$ = Angle of rotation = 40 rev

t = Time taken

Equation of rotational motion

$\omega_f^2-\omega_i^2=2\alpha \theta\\\Rightarrow \alpha=\frac{\omega_f^2-\omega_i^2}{2\theta}\\\Rightarrow \alpha=\frac{0^2-1.5^2}{2\times 2\pi \times 40}\\\Rightarrow \alpha=-0.0047\ rad/s^2$

Acceleration while slowing down is -0.0047 rad/s²

$t=\frac{\omega_f-\omega_i}{\alpha}\\\Rightarrow t=\frac{0-1.5}{-0.0047}\\\Rightarrow t=335.103\ s$

Time taken to slow down is 335.103 seconds

$\theta=\omega_it+\frac{1}{2}\alpha t^2\\\Rightarrow 20\times 2\pi=1.5\times t+\frac{1}{2}\times -0.0047\times t^2\\\Rightarrow 0.00235t^2-1.5t+125.66=0$

Solving the equation

$t=\frac{-\left(-1.5\right)+\sqrt{\left(-1.5\right)^2-4\cdot \:0.00235\cdot \:125.66}}{2\cdot \:0.00235}, \frac{-\left(-1.5\right)-\sqrt{\left(-1.5\right)^2-4\cdot \:0.00235\cdot \:125.66}}{2\cdot \:0.00235}\\\Rightarrow t=539.11, 99.18\ s$