If the Earth did not rotate, how much more would we weigh?

Question

If the Earth's rotation causes centrifugal force, pushing us away from it and decreasing our weight, how much more would we weigh if this centrifugal force were not present?

No insanus999, I'm not a Christian. And if my comprehension of the universe was that good, I wouldn't be asking questions here, would I? If yours was any good, I think you'd be trying to make a contribution and explain it, if you had the mental acuity to do anything but throw cheap, desperately unoriginal and unfunny insults at people here asking honest questions.

Answer 1

The centrifugal acceleration is w^2r , so lets see w is radians per second would be 2pi/(3600*24) = 7.26x10^-5 r in meters would be 4000miles * 1600 = 6.4x10^6

so the acceleration would be about .033 meters/sec^2 compared to the normal surface acceleration of about 9.8 m/sec^2 so your weight would only change by about .35% not much.

However there is another factor that is important. Because of the spinning the Earth bulges in the middle putting extra mass under the fastest spinning part. This would counteract the centrifugal force and cause the change to be less.

Answer 2

It can be calculated using the formula m R W^2 cos A x cos A

m- The mass of the object.

R- Mean radius of earth = 6371 x 10^3 m.

W- The angular velocity of earth = 0.7292 x 10^ (-4) radian per second.

A- The latitude at that place.

At the equator it increases by 1/300 of its present weight.


If the Earth’s rotation is not taken into consideration, a body lying on the surface of earth can be considered at rest. The sum of the forces acting on the body would then be equal to zero.

As a matter of fact, any particle lying on the Earth’s surface at latitude A, moves with an angular velocity W = 0.7292 X10^(-4) radian per second about the globe’s axis, i.e., in a circle of radius r = R cos A.

Therefore the sum of the forces acting on such a particle differs from zero. A force
m R W^2 cos A is directed along r.

Resolving this force into two components, the component m R W^2 cos A x cos A
is pressing the earth and hence the reaction force of earth acts in the opposite direction. (Few says that this force is centrifugal force even though it is not correct; it is because for circular motion only centripetal force is needed)

By this amount the weight of the body is reduced. If earth stops rotation the weight will increase by this amount.

Since at the pole the angular velocity is zero, a body has the maximum weight at the poles.

Thus another simple way of calculating the increase of weight if spin of earth is stopped is to find the difference in weight of an object at a place and the weight of an object at the Pole.

Increase in weight = m (g - g’). Where g is the acceleration due to gravity at Pole and g’ is the acceleration due to gravity at the place.


To understand how the weight will increase if there is no spin of earth, imagine an object at the equator.


It is pulled toward earth by an acceleration of g = 9.8m/s^2.

If it rotates around the earth (radius of circle 640000m) then it will not press the earth. We can calculate the angular speed needed.

Centripetal acceleration = g = 9.8 m/s^2. = R W W = 640000 W W.

W = 39 x 10^ (-4) radian per second.

If an object spins the earth with this angular speed the it will move along a circle of radius 6400 k/m. That is, it will not press the earth.

But since the angular speed is only 0.7292 x 10^ (-4) radian per second, it presses the earth.

If the angular speed is reduced to zero then it will press the earth with maximum force.

Answer 3

This ? came up a few weeks ago and has a simple answer. At the north or south pole, you would weigh the same, because there is no motion there even when the earth is turning. As you approach the equator, you weigh more and more, but the amount even right at the equator comes to only about 0.3% heavier than with rotation.
Also, I've not taken into account that the earth bulges at the equator, so you'd be a bit farther from the center than at the poles, but this is a negligible effect.

Answer 4

human beings or any materialistic creation contained in the international will obey the 2d regulation of thermodynamics. it must be stated interior the following way " contained in the attitude of creating complicated molecules from basic ones, some volume of usable ability is lost as warmth ". human beings, being produced from the earthly aspects, consequently, must have ate up more effective than what they weigh. this can convey about lack of earth's weight contained in the perfect 2000 years. yet, the earth keeps receiving ability from the solar for the perfect 2000 years. this may upload to its weight. a level of those 2 strategies will let us know the change in earth's mass. this may decide on one area of the question. i do not study the outcome of weight on the rotation of an merchandise.

Answer 5

I can't believe the rot I'm reading here.

Facts:
1. We are on earth because of its gravity. Not because it is spinning. The earth stopping to spin will NOT cause us to "fall into space"
2. We still would have day and night if the earth stopped spinning due to its orbiting the sun. Only they would be much longer. (measured in months)

3. A centrifugal force would INCREASE our weight. If you wanted to test it tie a hook of the spring balance on a string and whirl it around your head. The reading will be more than zero.

4. The difference in weight if the earth stopped spinning is not very significant (less than 10% definitely)... likely to be around 1%.

Answer 6

Gravitational force is due to the Earth's mass, and not due to it's rotation. The moon is 1/6 the size of the Earth. When astronauts went to the Moon the weighed 1/6 their weight on Earth.

Answer 7

the huge size of the earth exerts a gravitational force that pulls everything within the boundary of that force to the centre of the earth. That is what keeps from floating merrily off into space.
The earth revolves at 64,000 mph. Centrifugal force would cause us to fly off into space, if not for the force of gravity pulling us back.
If the earth suddenly stopped, it would be the equivelent of a car crash at 64,000mph. It would be very very messy. Not only would we and all life be mushed, the very crust would leap off the planet like a toupee in a high wind.
There must be an equilibrium between these two forces for life to exist - if only gravity existed we would be crushed to the ground by the weight of the earth - basically we would weigh the same as the earth; and if the centrifugal force was all that existed then we would not exist as the planet would itself have disintegrated to a size where the centrifugal force would not have anything to work on.

Answer 8

Your notion that "centrifugal force" pushes us away from the earth and decreases our weight is incorrect.

Any object that is in uniform circular motion requires a non-zero net force to cause it to change its direction of motion. That force must be directed toward the center - not away from it. What people refer to as "centrifugal force" is the tendency of a body in motion to continue in motion until another force acts on it. When that force acts on it, it causes the direction of motion or speed to change.

Now, on earth, gravity provides the force that causes objects to remain in uniform circular motion instead of flying off into space. But there is no "centrifugal force." Instead, an object at the surface has a force of gravity pushing down, a "normal" force or reaction force (i.e., the force of the surface of the earth pushing back to counteract the force of the object on the surface). The normal force will be slightly less than the weight of the object because there must be a net force directed toward the center of the earth to keep us in motion.

So, the answer to your question is that we weigh the same because there is no centripetal force. However, the earth pushes back on us with a little less force than our weight because of the need to have a nonzero net force to keep us in uniform circular motion.

We can calculate the amount of the difference from the equation F = ma=mv^2/r where m is our mass, v is the tangential velocity of the earth's surface (perhaps 800 or so miles per hour depending on latitude) and r is the radius of the earth. But that is not due to any "centrifugal force."

Answer 9

Rotation of an object has nothing to do with it's force due to gravity. We'd still 'weigh' the same. After all, we always have mass, but not always a gravity to go along with it (astronauts outside the gravitational pull of the earth).

Answer 10

oh i worked this out once, uh a=v^2/r v= 12764 km x pi =40074 / 24 = 1669 km /h 1669000m/h =1669000/3600= 464ms-1 x 464ms-1= 215116 / 6378000 =0.03373ms_2 so so thats g=9.81ms-2 + 0.03373ms-2 = new g=9.8437ms-2 so if you will weigh more by this amount,