Why do we rotate along with the earth's rotation?

Doc Al

I'll accept that for the moment.
Again, a person who is 'at rest' is meaningless. Do you mean a person on earth who is at rest with respect to earth? If so, then the relative speed is 5 mph, of course.
The force needed to change one's velocity depends on (1) how big a change you want and (2) how fast you want to change.

D H

Stop using text-speech, singh94. The correct wording is you rather than u, I rather than i, what rather than wat, are rather than r.

singh94

i mean a person who is in space. if everything was not moving(not at respect to eachother but in actual) then he would be at rest with respect to them. now do u get it

finally i am on earth and moving with the earth constant speed of 1000 miles. if i move in opposite direction at a speed of x miles per hour and i reach the speed in 1 second then why dont i need a force of which can give me a speed of 1000+x miles in opposite diretion in 1 sec. otherwise i have two different velocities at same time 1000 miles in earth direction an five miles in opposite direction which is not possible

singh94

Gee i didn kno dat :)

JaredJames

No, you don't have two velocities.

You are either travelling at 1005mph east or 995mph east. Put simply, you are always travelling east unless you are going faster than 1000mph in a westerly direction.

Doc Al

Just being 'in space' does not determine an object's velocity. It can have any allowable speed.
OK.
Once again, a force is not associated with a velocity, but with a change in velocity. And that's only x mph.

As far as your velocity is concerned, that depends on what you are measuring it with respect to. With respect to the earth's surface, it would be x mph. With respect to the earth's center, it would be 1000 + x mph. With respect to the Sun, something else entirely. And so on.

singh94

yes u r right.

JaredJames

I didn't know that
you are

Really? Asking for trouble after being warned.

singh94

change in velocity is being 1000miles in east to 5 miles in west. also with earths center my v would be zero as the displacement is zero.

singh94

i dont kno wether it is u jarednjames or the original person but know that u cant force me to stop writing in short forms just cause u dont like it. either u bear with me, or u ignore me but stop trying to bully me OK?

Doc Al

Huh? Are you moving 5 mph with respect to the surface or 1005 mph? Kind of makes a difference.

Huh? The surface of the earth is moving with respect to the center at 1000 mph. (Roughly speaking, at the equator.)

JaredJames

Forum rules say you can't, you agreed to them on signing up.

Doc Al

Think twice about continuing to violate our rules.

singh94

allright then if that is the case ill stop imediately but i may make some slips here or there.

singh94

i APOLOGISE TO DOC AL JADERNJAMES AND ALL WHO TOLD ME TO STOP WRITING IN SHORT FORMS.
SORRY

singh94

the earth is rotating the center may not move from its position but it is also rotating if u take the earth and shrink it to the size of the center of the earth then it would still rotate right? so the position of a point on earths surface to the center remains same.

Doc Al

No. Imagine a wheel spinning on its axle. The axle is fixed--its speed is zero (with respect to some frame). But the rim of the wheel is moving with respect to that frame. Same with the earth.

(Don't confuse rotational speed with translational speed.)