Why does a straw look bent in water?

[Sigmarus]

I know it's related to the basics of refraction,but would like to know more in-depth!Thanks!

[imatfaal]

Are these homework questions?  Are you a bot? Are you asking then answering questions from another site?  This sudden flurry of one line questions is a bit weird.

[Sigmarus]

Nope!Apparently i have to seperate some questions from a previous post of mine(request from moderator).And nope this aren't homework questions.

Sorry for the misunderstanding!

[Sensei]

I would suggest getting 3D application such as f.e. Blender. It's free. Then make box (it's be water, make diffuse color blue), and long thin cylinder (it's be straw, make diffuse color green). Place camera in such way to see them both. Enable real-time previewing. And start adjusting transparency, and then refractive index parameters, to see what they have effect.

Add to it procedural texture displacement of water object, to simulate waves, ripples on the surface of water.

Even in 3D application, simulating reality, it'll bend.

 

Edited August 3, 2017 by Sensei

[Sigmarus]

But is there any scientific reason for this phenomenon?

[petrushka.googol]

Refraction is responsible (which is caused by different speed of light in different (air / water) media).

[iNow]

^Speed of light is constant. Only the "apparent" speed of light changes since the photons interact with more molecules in water than in air

[swansont]

3 minutes ago, iNow said:

^Speed of light is constant. Only the "apparent" speed of light changes since the photons interact with more molecules in water than in air

There's some semantics here, muddling the physics.

Speed of photons is constant. The speed of light in a medium varies with the index of refraction. There's nothing wrong with saying light propagation slows in a medium; it takes longer for light to exit a medium compared to the same distance in a vacuum. There's noting "apparent" about that. The classical explanation is that the wavelength changes owing to the different values of permeability and permittivity; their product gives 1/v^2

The constant value (more technically, the invariant value) is the speed of light in a vacuum, which is c. It's wrong to say c varies, but not wrong to say the speed of light varies. 

[iNow]

Thanks for the clarification. I'll need to update my phrasing and thinking accordingly

[swansont]

3 hours ago, iNow said:

Thanks for the clarification. I'll need to update my phrasing and thinking accordingly

Like I said, it's semantics. Whether you mean "speed of light propagation in a medium" or "speed of light in a vacuum" sometimes has to be discerned from context. It's the kind of sloppiness one gets with an attempt at brevity from using jargon. One physicist saying it to another is unlikely to cause a problem, but if you aren't as well-versed, it can cause conceptual issues. And in equations, it's easy figure it out. One is c/n, the other is c.

Luckily there are people here who can translate.