- #1

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Einstein:

You do not really understand something unless you can explain it to your grandmother.

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- Thread starter ruko
- Start date

- #1

- 57

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Einstein:

You do not really understand something unless you can explain it to your grandmother.

- #2

- 93

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It would take an infinite time

It is not possible to accelerate and reach the speed of light

It is not possible to accelerate and reach the speed of light

- #3

- 501

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v=vo+at

c=gt

t=c/g

t=(3*10^8 m/s) / (10 m/s^2)

t = 3*10^7 s

That's just about one earth year.

- #4

mgb_phys

Science Advisor

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You can use this with the normal acceleration formulae to work out, with a constant force, how you will accelerate.

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- #6

DaveC426913

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You would need to specify from whose frame of reference that constant acceleration is measured.If you specify a constant acceleration you 'could' accelerate to the speed of light.

- #7

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Vf = Vi + AT

T = Vf - Vi / A

T = ((299792458) - (0)) / (9.8)

T = 30591067.14 seconds or 354 days.

- #8

DaveC426913

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No. This is NOT correct.

Vf = Vi + AT

T = Vf - Vi / A

T = ((299792458) - (0)) / (9.8)

T = 30591067.14 seconds or 354 days.

It is only true at speeds well below c. Nearer c, the acceleration levels off. The correct formula is 1/sqrt(1-v^2/c^2).

After x years of 1g acceleration you will be travelling at a velocity of y:

Code:

```
years accel velocity
1 0.77c
2 0.97c
5 0.99993c
8 0.9999998c
12 0.99999999996c
```

Note that, after one year, you are only doing 3/4ths of c. It's not until 2 years that you near c.

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- #10

DaveC426913

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And in response to the original question, the reality of the matter is that no one is entirely sure what happens because examples of particles with mass that move at or near the speed of light are very uncommon and rarely weigh more than an electron.

Not sure where you get your information from but we are

- #11

russ_watters

Mentor

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Satellites go plenty fast enough for the effects of SR to be measured.And in response to the original question, the reality of the matter is that no one is entirely sure what happens because examples of particles with mass that move at or near the speed of light are very uncommon and rarely weigh more than an electron.

- #12

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No. This is NOT correct.

It is only true at speeds well below c. Nearer c, the acceleration levels off. The correct formula is 1/sqrt(1-v^2/c^2).

c.

One year is mathematically correct if you could somehow

- #13

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What does 1G even means when both 1 meter and 1 second are affected by GR effects ?

- #14

DaveC426913

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The occupantOne year is mathematically correct if you could somehowone G throughout the significant relativistic phase of the trip.maintain

- #15

DaveC426913

Gold Member

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Well, since the OP never mentioned we were doing this within a deep gravity well, we can ignore GR effects.What does 1G even means when both 1 meter and 1 second are affected by GR effects ?

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