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Between you and me, lets see who can pick the fastest moving thing.
Well, what did you choose?
Cheetah? Buggati Veyron?
Sorry, but you are out of luck,
because I choose RX-J0822-4300.
This baby is a star that travels 5.4 million km per hour!
It is also known as the "Cosmic Cannonball".
Are you impressed?
I know I am being unfair, picking something that few people knew.
How about this, round 2,
lets see who can pick the fastest thing that really, near us.
I pick Earth!
That's right,
earth is orbiting the sun with the speed of 30km per second,
it's "a little bit" faster than your car.
Now imagine, in one minute,
the Earth is going to race "Cosmic Cannonball" to a straight line forward race.
And we earthling want to accelerate Earth to the same speed as "Cosmic Cannonball",
before the race.
How fast do we need to accelerate the Earth?
First of all, let me introduce some tool to help you finish the job.
We all know that acceleration means how fast something speed up in a second.
Hence the formula a=v-u over t.
Just to be sure you know,
"a" is a notation for acceleration,
v for final velocity,
u for initial velocity,
and t of course for time.
We can also play around with the formula and get few other definition out of it:
for example,
if we configure it to explain the final velocity,
we get that:
final velocity is initial velocity plus "acceleration" multiplies by "duration acceleration".
Or we can configure it to explain time, it will be:
"how many seconds you need" is "how much velocity difference you want" divided by "how many difference you make per second"
In this particular problem,
I will just simply use a=v-u over t,
since all i want to do is to find the acceleration.
So now that we have the formula in arsenal,
lets list down our assets.
Now, our object of interest is the earth,
we want to accelerate it to the velocity of "cosmic cannonball",
so all of the value that was listed should be of the Earth's.
Initial velocity of Earth is 30 km per second, forward.
Do you notice how I include the direction in this velocity?
It is because that velocity is a vector quantity,
and to fully describe it,
we need to have both magnitude and direction.
Is it important in this case?
Hell no,
I just don't want to have someone complaining that I didn't do things by the book.
And to play by the book,
lets use SI unit for our calculation.
Now THIS is important!
Lets convert 30km per second into meter per second,
which we will get thirty thousand meter per second.
Now, the final velocity,
the velocity that you want Earth to have
is the speed of "Cosmic Cannonball",
which is 5.4 million km per hour, forward of course.
To convert km per hours,
we multiply 1000 to convert km to m,
and divide 60 to convert hour to minutes,
and divide another 60 to convert minute to second.
Like this (Video, Now, Thanks).
And we will get 1 500 000(1.5million) meter per second.
Forward of course.
Now,
the time we have to accelerate the Earth is 1 minute.
Means 60 seconds.
Now lets do the magic!
a=v-u divided by t,
substituting the values, and the answer is:
24 500meter per second square.
and the direction of the acceleration is?
not towards left, not towards right,
but forward of course.
Well.. this speed of acceleration is really intense.
It's too intense...
Earths gravity is only 9.8 meter per second square,
the speed of acceleration that you calculated is 25 thousand times the gravitational force of Earth...
What will happen?
Perhaps people on one side of the Earth will be flatten by the force,
while the others will be swung away from the Earth.
And If Earth are still orbiting the sun in that speed,
maybe... 1 year would means 20minutes now?
Or maybe Earth will just simply disintegrate?
I am neither a Physicist nor a Astronomist,
but my guess is:
we all will die, hehe.
Ermmm, to prevent the distruction of the Earth,
let's postpone the race a while longer --
and accelerate the Earth in a slower rate.
Lets say, half a G(earth's gravity)?
means 5 meter per second.
I wonder how long will it take?
Now, this time, we are trying to find t. (t=?)
v and u is still the same as previous question.
And a= 5ms-2 now
Now, lets configure the formula to find t.
Simple,
just switch the place of a and t.
Substitue the value, and we will get the answer.
TADAH!
looks like it will take 294 000 seconds.
Meaning,
4900 minutes.
81 hours,
or
3 and a half day.
Hmm,
it's actually a lot faster than I've aspected.
But I think we all will still all die if Earth is moving that fast.
So.... lets just cancel the race.
Peace!