Speed of Light


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Emmanuel Ogunrinde 3L
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Joined: Fri Sep 28, 2018 12:24 am

Speed of Light

Postby Emmanuel Ogunrinde 3L » Sun Oct 14, 2018 1:54 am

Is speed of light a constant (3*10^8) or does it ever change?

Clarissa Nava 3H
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Re: Speed of Light clarissa nava 3H

Postby Clarissa Nava 3H » Sun Oct 14, 2018 3:40 am

It does not change it will always be 3*10^8

AustinGrove3B
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Re: Speed of Light

Postby AustinGrove3B » Sun Oct 14, 2018 11:55 am

more specifically 2.99792 x 108. I think in the book they use this (more sig figs) than 3.0 x 108

Maya_Peterson1C
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Re: Speed of Light

Postby Maya_Peterson1C » Sun Oct 14, 2018 11:57 am

I did some research behind it, and some sources are claiming that recent studies show light doesn't always travel at the speed proposed by Einstein's theory. However, for the purposes of this class the speed of light is assumed to be constant.

Manya Kidambi 3I
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Re: Speed of Light

Postby Manya Kidambi 3I » Sun Oct 14, 2018 12:03 pm

You should treat it as a constant in any sort of calculations done for this class. I’m sure for higher level chemistry this would be different, but at this point I wouldn’t worry.

Ruiting Jia 4D
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Re: Speed of Light

Postby Ruiting Jia 4D » Sun Oct 14, 2018 2:22 pm

AustinGrove3B wrote:more specifically 2.99792 x 108. I think in the book they use this (more sig figs) than 3.0 x 108


Would it be advisable to calculate using 2.99792 x 10^8 on the exams? I'm not sure when to apply significant figures - either throughout the problem or just for the final answer.

404817859
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Re: Speed of Light

Postby 404817859 » Sun Oct 14, 2018 3:04 pm

sig figs will give more of an precise answer, either way should work :)

405098546
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Re: Speed of Light

Postby 405098546 » Sun Oct 14, 2018 3:42 pm

For the purposes of this class the speed of light probably will always stay the same. Though I think in certain mediums like water or glass the light of speed can change.

Dhwani Krishnan 1G
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Joined: Fri Sep 28, 2018 12:17 am

Re: Speed of Light

Postby Dhwani Krishnan 1G » Sun Oct 14, 2018 3:58 pm

the speed of light changes with the medium, in air it is 3.0x10^8m/s.

Timothy_Yueh_4L
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Re: Speed of Light

Postby Timothy_Yueh_4L » Sun Oct 14, 2018 4:28 pm

Just wanted to add that the speed of light is constant throughout the entire electromagnetic spectrum (~3.00 * 10^8 m/s)

Diana Sandoval 1K
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Re: Speed of Light

Postby Diana Sandoval 1K » Sun Oct 14, 2018 4:58 pm

It's assumed to be a constant and from my knowledge I believe we will be given the constant.

Anjali 4A
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Re: Speed of Light

Postby Anjali 4A » Sun Oct 14, 2018 5:01 pm

Will we be provided all of these constants/equations during the tests, midterms and final?

Danny Zhang 4L
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Joined: Fri Sep 28, 2018 12:26 am

Re: Speed of Light

Postby Danny Zhang 4L » Sun Oct 14, 2018 5:55 pm

Anjali 4A wrote:Will we be provided all of these constants/equations during the tests, midterms and final?


I am sure that we will get a cover sheet with all of the constants/equations as we did on the first test on all future tests as well.

Connie Chen 3D
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Joined: Mon Jan 08, 2018 8:12 am

Re: Speed of Light

Postby Connie Chen 3D » Sun Oct 14, 2018 9:06 pm

The speed of light is a constant, therefore it will never change. You can, however, convert it to other units if you wish, as long as all the correct units cancel out.

janessadai 1F
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Re: Speed of Light

Postby janessadai 1F » Mon Oct 15, 2018 9:07 am

The speed of light is always constant, and we are provided the value during tests and exams so we can just use whatever value they give us

isarose0
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Re: Speed of Light

Postby isarose0 » Mon Oct 15, 2018 11:48 am

The speed of light is constant and will not change, there may be a more specific value, however, it is most commonly known as 3x10^8 m/s

Aleeque Marselian 1A
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Re: Speed of Light

Postby Aleeque Marselian 1A » Mon Oct 15, 2018 4:02 pm

I'm pretty sure that for this class, we treat the speed of light as a constant all the time.

405098546
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Re: Speed of Light

Postby 405098546 » Sat Dec 08, 2018 11:15 pm

Speed of light is constant

davidryan3f
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Joined: Fri Sep 28, 2018 12:23 am

Re: Speed of Light

Postby davidryan3f » Sat Dec 08, 2018 11:16 pm

light always travels at the same speed regardless of wavelength or amplitude. it is a constant.

Zachary Menz 1D
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Joined: Wed Nov 07, 2018 12:17 am

Re: Speed of Light

Postby Zachary Menz 1D » Fri Jul 05, 2019 2:38 am

The speed of light is constant, and is represented in class as c = 3.00 x 10^8 m/s

Radha Patel 1A
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Re: Speed of Light

Postby Radha Patel 1A » Sun Jul 07, 2019 5:40 pm

The speed of light is constant, it helps maintain the equation c= wavelength x frequency by allowing wavelength and frequency to be inversely related.

Sisi Li 1F
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Joined: Mon Mar 11, 2019 12:15 am

Re: Speed of Light

Postby Sisi Li 1F » Sun Jul 07, 2019 6:34 pm

In the context of this class, it should always be treated as a constant.

Shutong Hou_3I
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Re: Speed of Light

Postby Shutong Hou_3I » Wed Oct 02, 2019 9:43 pm

The speed of light is constant in vacuum, and the speed is 3*10^8 m*s^-1, which would also be generally used in solving general problems. However, the speed would actually be a little bit slower when there is air, whereas we generally ignore this difference between the idea and the fact in our calculations for this course.

alexfwang3g
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Joined: Thu Jul 11, 2019 12:16 am

Re: Speed of Light

Postby alexfwang3g » Thu Oct 03, 2019 11:21 am

The speed of light is always constant.

Ashley Fang 3J
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Joined: Fri Aug 30, 2019 12:17 am

Re: Speed of Light

Postby Ashley Fang 3J » Fri Oct 04, 2019 12:58 am

Speed of light is a constant and will be given during tests/exams.
The link of the constants and equations sheet is on his website but I'll link it here!

https://lavelle.chem.ucla.edu/wp-conten ... ations.pdf

Brandon Tao 1J
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Joined: Sat Aug 17, 2019 12:15 am

Re: Speed of Light

Postby Brandon Tao 1J » Fri Oct 04, 2019 8:12 am

It does not change, so it is a constant

skim313
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Re: Speed of Light

Postby skim313 » Fri Oct 11, 2019 4:04 pm

3.00 x 10^8 is the speed of light inside a vacuum.

Natalie C 1K
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Re: Speed of Light

Postby Natalie C 1K » Fri Oct 11, 2019 6:08 pm

the speed of light is constant ! because it will never change

Rohan Kubba Dis 4B
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Re: Speed of Light

Postby Rohan Kubba Dis 4B » Sat Oct 12, 2019 1:31 pm

Unless we are not in a vacuum, the speed of light will stay constant at 3.0 x 10^8 m/s.

HuyHa_1D
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Joined: Wed Sep 11, 2019 12:15 am

Re: Speed of Light

Postby HuyHa_1D » Sat Oct 12, 2019 4:31 pm

The speed of light won't because it's a constant but sometimes they might be displayed differently due to sig figs and rounding and whatnot.

Merin Padayatty 3G
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Joined: Thu Jul 11, 2019 12:16 am

Re: Speed of Light

Postby Merin Padayatty 3G » Sat Oct 12, 2019 7:33 pm

The speed of light is a constant as it doesn't change.

Sally Qiu 4l
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Joined: Fri Aug 30, 2019 12:18 am

Re: Speed of Light

Postby Sally Qiu 4l » Sat Oct 12, 2019 7:38 pm

the speed of light changes depending on the medium it is traveling through; however, the constant 3.00x10^8 m/s is used when assuming the light is traveling through a vacuum. therefore, in our case, the speed of light is constant.

Rodrigo3H
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Joined: Sat Jul 20, 2019 12:16 am

Re: Speed of Light

Postby Rodrigo3H » Sat Oct 12, 2019 7:41 pm

The speed of light is a constant so you don't have to worry about it changing.

Emil Velasco 3I
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Joined: Wed Nov 21, 2018 12:19 am

Re: Speed of Light

Postby Emil Velasco 3I » Sat Oct 12, 2019 9:00 pm

The speed of light (3. 10^8 m/s) will always be a constant.

Pablo 3I
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Joined: Sat Feb 02, 2019 12:15 am

Re: Speed of Light

Postby Pablo 3I » Sat Oct 12, 2019 9:57 pm

No need to worry for the sake of problems, light constant will not change.

Brian J Cheng 1A
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Joined: Thu Jul 11, 2019 12:15 am

Re: Speed of Light

Postby Brian J Cheng 1A » Sat Oct 12, 2019 10:05 pm

For the purpose of this class we'll assume the speed of light (c) to be roughly 3.00 x 10^8 m/s. Light travels at different speeds through different mediums, but we'll use the vacuum measurement for our calculations

Gilberto Millan 1F
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Joined: Sat Aug 03, 2019 12:15 am

Re: Speed of Light

Postby Gilberto Millan 1F » Sat Oct 12, 2019 11:09 pm

This is also something that I was considering. Using the constant as 2.998*10^8 m/s, the book gives two examples of determining wavelengths on page 5. I was wondering why they didn't give any background information on the constant? But overall the responses were helpful.

Rosa Munoz 4D
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Joined: Wed Sep 18, 2019 12:21 am

Re: Speed of Light

Postby Rosa Munoz 4D » Sat Oct 12, 2019 11:13 pm

It is a constant.

705379941
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Joined: Fri Aug 30, 2019 12:16 am

Re: Speed of Light

Postby 705379941 » Sat Oct 12, 2019 11:59 pm

speed of light is a constant!

Trent Yamamoto 4I
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Joined: Sat Aug 17, 2019 12:18 am

Re: Speed of Light

Postby Trent Yamamoto 4I » Sun Oct 13, 2019 12:01 am

The speed of light is a constant (3*10^8) and is always reflected as so on the constant sheet.

Amir Bayat
Posts: 45
Joined: Sat Sep 07, 2019 12:16 am

Re: Speed of Light

Postby Amir Bayat » Sun Oct 13, 2019 12:03 am

The speed of light will not change. It is consistently 3.8 *10^8.

Lara Kristine Bacasen 3B
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Re: Speed of Light

Postby Lara Kristine Bacasen 3B » Sun Oct 13, 2019 12:18 am

C is a constant but of course although it is widely accepted this constant assumes particular conditions like how light particles has no resting mass. There is also quantum field theory that argues the vacuum isn't always empty and has elementary particles that pop in and out if existence which can cause changes in the speed of light.


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