if i put an object into the sea. a golf ball for example, would that raise the whole sea level. even if it was extreamly small?

The ice that melts in Antarctica and in Greenland as a result of global warming will redistribute into the oceans of the world.  This will involve redistribution of many gigatonnes of mass from the polar regions (close to the earth's axis) to the average latitude of the earth's oceans (further from the earth's axis). This means that to conserve angular momentum the earth should reduce its spin rate.  Has this occurred and if so what is the magnitude of the effect; A - Now - and B - when all the polar ice has melted?

Hello,

I've just added a picture to try to explain what this old OU program was showing :-)

I’ve just watched a TV documentary attempting to explain plate tectonics. Whilst this and many others show well the creation of the plates at the Mid Atlantic Ridge, they do not explain why they are also sliding left and right along fracture zones across the ridge.

 I remember seeing a long time ago, an old ‘OU’ black and white TV programme saying that these fractures form concentric rings right around the earth sliding past one another.

Can anyone explain why this is the case and why also, these seemly important movements are not considered in future predictions of how the plates may well look in the distant future?

Thanks,

Daniel.

if the earth is rotating at 1200mph clockwise for example, and a plane was traveling at 1200mph clockwise, would the people on the plane feel weightlessness, would there be no gravity on the plane?

Im not sure how to interpret the idea from my head into words but i will try my best. Say everyone was holding hands in a straight line all the way around earth so that they joined. wouldnt that mean, taking into consideration the earths shape, that the line would always be in the centre of the earth?

furthermore if there was another line of people holding hands but lets say they was 1000 miles for example away, (thinking of for example a football, if you had a band in the middle of the football the diametre could for example be 30cm where as if the band was placed further apart it could be 15cm as it would be near the edge; could this idea be the same if the football was earth, and the bands where people?) would the people 1000 miles away contain for example 10 million people where as in the middle it would be 100 million because of a longer distance to travel? tell me if im talking nonsence or if you understand my concept?

Or is it an optical illusion?

I have read today that Newcastle University plan to drill a hole 2000m down to extract heat from the earth. My question is if this begins on an industrial scale, are there any consequences to all the heat being removed from the earth? Is it just the depth of the core that keeps it hot as it is well insulated? Do we know how much energy is down there?