## speed of light

$c=\lambda v$

nehashetty_2G
Posts: 102
Joined: Thu Jul 25, 2019 12:15 am

### speed of light

Does the speed of light always stay the same? If not, under what circumstances can it change?

Kimberly Koo 2I
Posts: 99
Joined: Sat Aug 17, 2019 12:17 am

### Re: speed of light

No the speed of does not remain constant, a case where it changes is when it goes through multiple different mediums.

philipraj_1F
Posts: 52
Joined: Fri Aug 30, 2019 12:16 am

### Re: speed of light

I think that the speed of light changes depending on the material it travels through. Light moves slower through denser materials as particles can get in its way.

Frederick Keith_4C
Posts: 65
Joined: Thu Sep 26, 2019 12:19 am

### Re: speed of light

Yeah just to add on, the speed of light does change when passing from medium to medium. But the fastest it can be is the value we denote as "c" (3.00 x 10^8 m/s), which is when it is travelling in a vacuum.

Drake Choi_1I
Posts: 58
Joined: Sat Aug 17, 2019 12:15 am

### Re: speed of light

I remember learning in physics something about mediums and light. I know that a vacuum is where light can travel fastest. What is the next fastest medium?

Anika Chakrabarti 1A
Posts: 102
Joined: Sat Aug 24, 2019 12:17 am

### Re: speed of light

I think for most of the problems we'll be doing this quarter we can just assume that C = the speed of light in a vacuum.

Anna Heckler 2C
Posts: 102
Joined: Wed Sep 18, 2019 12:18 am

### Re: speed of light

For the intents and purposes of this class, the constant for the speed of light, c, always equals 3.00 x 10^8. However, it is important to note that the speed of light is not constant as it moves from medium to medium. When light enters a denser material, the speed and wavelength of light decrease while the frequency stays the same.

gferg21
Posts: 51
Joined: Sat Aug 17, 2019 12:17 am

### Re: speed of light

When talking about a vacuum, it essentially means that that is how fast light travels through space, and is very similar but not exactly the same on earth when light is traveling through the air.

Maika Ngoie 1B
Posts: 97
Joined: Fri Aug 02, 2019 12:16 am

### Re: speed of light

Throughout this quarter, and for the purpose of this class, the speed of light will remain a constant equal to 3.0 x 10^8 m.sec^-1, however outside of this setting, it is not so absolute, and actually changes relative to the the mediums it travels through.

Maika Ngoie 1B
Posts: 97
Joined: Fri Aug 02, 2019 12:16 am

### Re: speed of light

Drake Choi_1I wrote:I remember learning in physics something about mediums and light. I know that a vacuum is where light can travel fastest. What is the next fastest medium?

I believe water is the next fastest at about 2.25 x 10^8 m.sec^-1, but we'll mainly be working with light in a vacuum

Amanda Mei 1B
Posts: 109
Joined: Sat Aug 24, 2019 12:16 am

### Re: speed of light

The speed of light in a vaccuum is 3.00x10^8 m/s. It is slower in mediums like air, water, and glass. I think that for this class we'll just use this value.