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3 years ago

They don't have an Astronomy Section and I believe that this falls the closest to Physics

1 answer:

5 0

The only thing we know of so far that can shift light to longer wavelengths is the "Doppler" effect. If the source and the observer are moving apart, then the observer sees wavelengths that are longer than they should be. If the source and the observer are moving toward each other, then the observer sees wavelengths that are shorter than they should be. It works for ANY wave ... sound, light, water etc. The trick is to know what the wavelength SHOULD be. If you know that, then you can tell whether you and the source are moving together or apart, and you can even tell how fast. If the lines in a star"s spectrum are at wavelengths that are too long, then from everything we know right now, the star and Earth are moving apart.

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A ray of light travels from a glass-to-liquid interface at an angle of 35.0º. Indices of refraction for the glass and liquid are

UkoKoshka [18]

Answer:

The angle of refraction for the ray moving through the liquid is = 32.3°

Explanation:

Refractive index of liquid (n₁/n₂) = sini/sinr

∴ n₁/n₂ = sini/sinr ................ equation 1

n₁ = index of refraction for glass, n₂ = index of refraction for liquid

Where i = incident angle of the first medium, r = angle of refraction or angle in the second medium.

Since the light ray is traveling from glass - to - liquid, the first medium is glass and the second medium is liquid. and the refractive index will be that liquid with respect to glass.

using the equation,

n₁/n₂ = sini/sinr

i = 35° , n₁ = 1.52, n₂= 1.63

Making sinr the subject of the equation above,

sinr = sini/(n₁/n₂)

sinr = sin35(1.52)/1.63

sinr =0.574(1.52)/1.63

sinr = 0.535

Taking the sin inverse of both side of the equation

sin⁻¹(sinr) = sin⁻¹(0.535)

∴ r = 32.3°

The angle of refraction for the ray moving through the liquid is = 32.3°

The right option is (b). 32.3°

5 0

3 years ago

Thinking about an analogue clock, calculate the angular displacement in revolutions, radians and degrees for the following: • A

Inessa [10]

Answer:

1.047 rad

Explanation:

A secondhand makes a complete revolution (360 degrees) in 60 seconds, so it displaces 6 degrees for every second of elapsed time (360/60 = 6).

And in 10 seconds, it will make a displacement of 10 degrees (6 * 10 = 60).

Finally converting the result into Radians by multiplication with π/180.

5 0

2 years ago

An ice cube at 0°C is placed in a very large bathtub filled with water at 30°C and allowed to melt, causing no appreciable chang

Paladinen [302]

Answer:

C. The entropy of the system (ice plus water) increases because the process is irreversible.

6 0

2 years ago

What is the purpose of oil used in a car's engine?

Hoochie [10]

B) to reduce friction

5 0

2 years ago

Which of the following statements about horizons is true?. a. They are characterized by whether they are solid, liquid, or gas..

garik1379 [7]

<span>The answer is d. they are defined by their different physical features. A soil horizon is a layer in a soil profile. Horizons are defined by different physical features such as colour or texture. Other features include, structure and permeability. Each horizon is represented by a letter; A,B,C....</span>

3 0

3 years ago