# A Question on Notation (1 Viewer)

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#### GreenPrint

1. The problem statement, all variables and given/known data

If velocity = displacement (time)
or
.
x = dx/dt

were you put a dot above the x using newtons notation were you indicate a derivative with reference to time with a dot above the symbol

so I was like
speed of light = lambda (frequency)
or

lambda with a dot above it = d(lambda)d(frequency)

is this correct because this all the speed of light is? Sense frequency is simply 1/t?

c = lambda frequency
c = lambda/period
lambda (with a dot above it) = d(labmda)d(frequency)

I just never got newtons notation with the dot thing am I doing this correctly?

2. Relevant equations

3. The attempt at a solution

Last edited:

#### Inferior89

The dot is there for the derivative with respect to time only.

So
$$\dot{f} = \frac{d}{d t} f$$

#### Mark44

Mentor
1. The problem statement, all variables and given/known data

If velocity = displacement (time)
velocity is a quotient. The way you have it above, it looks like a product.
or
.
x = dx/dt

were you put a dot above the x using newtons notation were you indicate a derivative with reference to time with a dot above the symbol

so I was like
speed of light = lambda (frequency)
There's no deriviative involved here. The speed of light, c, is a constant.
or

lambda with a dot above it = d(lambda)d(frequency)

is this correct because this all the speed of light is? Sense frequency is simply 1/t?

c = lambda frequency
c = lambda/period
lambda (with a dot above it) = d(labmda)d(frequency)

I just never got newtons notation with the dot thing am I doing this correctly?

2. Relevant equations

3. The attempt at a solution

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