Speed of Light
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Re: Speed of Light
The speed of light will always be a constant and is labeled in equations as the variable "c". It is somewhere around 3.0 X 10^8 m/s. On exams, make sure to use the exact number for the speed of light that is given to you on the equation sheet of the exam. This will help you with getting the right number of sig figs and prevent any rounding errors.
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Re: Speed of Light
Yes. It’s a constant. Some might write it like 3.00 x 10^8 since it’s easier to remember
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Re: Speed of Light
pegahnasseri_3L wrote:The speed of light will always be a constant and is labeled in equations as the variable "c". It is somewhere around 3.0 X 10^8 m/s. On exams, make sure to use the exact number for the speed of light that is given to you on the equation sheet of the exam. This will help you with getting the right number of sig figs and prevent any rounding errors.
So just making sure but using 2.998 x 10^8 would be for your own accuracy and wouldn't get any points knocked off on an exam if we used 3.0 instead, right?
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Re: Speed of Light
The speed of light will always be 3.0 * 10^8 m/s in a vacuum. This value is a constant; however, the speed of light can vary depending on the medium it is passing through.
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Re: Speed of Light
The speed of light is in fact a constant. I used to use 2.9979*10^8 more often but figured 2.998*10^8 is more commonly applied in this class.
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Re: Speed of Light
Yes. It is a constant and is universally agreed/defined as the length traveled by light in a vacuum condition in 1⁄299792458 seconds.
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Re: Speed of Light
I always used 3.0*10^8 in high school but it's probably better to use the values from the constants and equations paper that is on Professor Lavelle's website.
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Re: Speed of Light
Sharon Rodriguez 3H wrote:pegahnasseri_3L wrote:The speed of light will always be a constant and is labeled in equations as the variable "c". It is somewhere around 3.0 X 10^8 m/s. On exams, make sure to use the exact number for the speed of light that is given to you on the equation sheet of the exam. This will help you with getting the right number of sig figs and prevent any rounding errors.
So just making sure but using 2.998 x 10^8 would be for your own accuracy and wouldn't get any points knocked off on an exam if we used 3.0 instead, right?
It all depends how technical your TA is with rounding as some TA's pay more attention to it than others. So to be sure just use that 2.88 x 10^8 so that you don't risk losing any points.
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Re: Speed of Light
The speed of light is a constant. I would use the value given on the equation sheet just to be safe.
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Re: Speed of Light
Yes that is the speed of light and it is a constant. But, for simplicity, it is also acceptable to use 3.0x10^8 m/s. This is one of the key concepts of the photoelectric effect and is necessary for understanding the correlation between light, its frequency, its wavelength, and its energy. Also keep in mind that it is the speed of light, so the constant may be used for velocity in some scenarios.
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Re: Speed of Light
Yes the speed of light is a constant and you can use 2.998*10^8 or 3.0*10^8 for its value.
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Re: Speed of Light
The speed of light is always a constant. It would be better to use the exact number provided on the equation sheet (2.99792*10^8) on the exams.
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Re: Speed of Light
Yes, the speed of light is always going to be 2.998 x 10^8 m/s. It is always going to be a constant too. Sometimes, it is rounded to 3.00 x 10^8 m/s; however, using 2.998 x 10^8 m/s is recommended for accuracy.
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Re: Speed of Light
The speed of light is a constant and is represented by the letter "c". It is approximately 3.0*10^8 m/s.
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Re: Speed of Light
Yes, it is a constant. Some prefer to write it as 3.00x10^8 or 2.998x10^8 believe it or not sometimes, depending on which one you use, it can change your answer slightly. So for accuracy try to use the 2.998x10^8. Then your final answer should be in the appropriate Sig figs :)
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Re: Speed of Light
For the purposes of this class I think we're best off using the value given to us on Lavelle's equation sheet
Re: Speed of Light
The speed of light is a constant (2.998 x 10^8) as others have mentioned 3.0 x 10^8 is sometimes used, however it would be better if you used 2.998 x 10^8 so that your sig figs at the end are correct.
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Re: Speed of Light
The speed of light is a constant, as seen through experimental data. For which version of the speed of light to use, my TA said to usually use 3.00*10^8 m/s, unless the constant/equation sheet or problem you are given says another number instead.
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Re: Speed of Light
Yes, the speed of light (2.998*10^8 m/s) is always a constant, as long as this light is traveling in a vacuum-like medium.
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Re: Speed of Light
I think it's better to use 3 x 10^8 instead of 2.998 x 10^8 simply because it's a whole and easier to remember. Most of the times the solutions usually use 3 x 10^8.Natalia Shahwan 4H wrote:is it better to use 2.998 or 3?
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