Unraveling Hubble Law and Integral: A PF Forum Guide

Stephanus
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Dear PF Forum,
I know this is a very basic, basic question. But I'd like to refresh my memory.
In Hubble Law.
##V = H_0 \, D##
##H_0## is Hubble constant, aproximately ##\frac{1}{3.1E17t}##
Okayy, let's say we alter those number to an easier number.
For every 10 metres, the velocity adds 1 m/s.
This is how we write, ok?
##V = 0.1\, D##
And now this.
If an object 1000 metres from us, speeding 100m/s, of course. What time does it takes to reach 4000 metres from us?
Time is Distance / Speed.
What is the formula?
Is this correct?
##\int_a^b \frac{H_0}{x}dx, a = 1000, b = 4000##
 
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##V=dx/dt## then ##dt=dx/V## then integrate it ##V=HD## İnside the integral will be ##1/H_0xdx##
 
Last edited:
RyanH42 said:
##V=dx/dt## then ##dt=dx/V## then integrate it ##V=HD## İnside the integral will be ##1/H_0dx##
Ahh, of course H0 is the divider, how careless I am!
Thanks.
 
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