The 20p Question Thread

[Eric Olthwaite]

It'll melt a long time before it gets to the core. A theoretical unmeltable weight, though, would overshoot the centre of the Earth a bit, but not all the way to NZ as it'd have lost energy to friction. Then it'd bounce back through the centre, part way back to Glossop and continue see-sawing smaller and smaller distances till it eventually settled in the centre.
edit: sorry, you said 'ignore friction'. If there were no losses then it would continue appearing alternately in Glossop and NZ forever.

It would basically act like a pendulum - and for broadly the same reasons - albeit in a straight line rather than through an arc?

 

[Ming the Merciless]

Talking of boring holes in the earth, if I bored a hole from Glossop, through the middle of the earth and out the other side and then I drop a weight into the hole, what would the weight do (assuming no friction)?
Would it just pop out in NZ or wherever, then zoom back in the opposite direction and reappear in Glossop?

It would melt and stay in the middle.

 

[Ming the Merciless]

Does a human heart ❤️ have a fixed number of lifetime beats?

 

[Eric Olthwaite]

Does a human heart ❤ have a fixed number of lifetime beats?

Eventually, yes.

 

[Ming the Merciless]

Eventually, yes.

Ah you misunderstand what lifetime beats means 🤪

 

[twentysix by twentyfive]

Ah you misunderstand what lifetime beats means 🤪

Is that like a lifetime guarantee?

 

[newfhouse]

Where has the potential energy it had when it left Derbyshire gone though? It'd turn into kinetic energy as it progressed, then momentum would keep it going past the centre till it all turned back to potential energy at a point equidistant from the centre of the earth to Glossop.

You’re probably right, assuming a spherical Earth with equal gravity distribution and no frictional or other losses in the hole. Sounds like a perpetual motion machine.

 

[Ming the Merciless]

Is that like a lifetime guarantee?

Well those only last 15 to 25 years. So I’d hope longer than that 😂

 

[Ming the Merciless]

Is Earth 2 hiding on the exact opposite side of the Sun?

 

[ebikeerwidnes]

You’re probably right, assuming a spherical Earth with equal gravity distribution and no frictional or other losses in the hole. Sounds like a perpetual motion machine.

Yup - if you ignore air resistance

which is normally one of the problems with perpetual motion machines

of course if you find a way to reduce air resistance to zero I think a Mr Brailsford would like to have a word

 

[lazybloke]

You’re probably right, assuming a spherical Earth with equal gravity distribution and no frictional or other losses in the hole. Sounds like a perpetual motion machine.

You're forgetting Earth's rotation, wobble, precession, elliptical orbit around the sun, the gravitational pull of other bodies, the solar system's rotation around the galactic centre, the increasing influence of Andromeda. I've forgotten what point I was going to make but probably means Librans will be lucky in love this week

 

[houblon]

Yup - if you ignore air resistance

which is normally one of the problems with perpetual motion machines

of course if you find a way to reduce air resistance to zero I think a Mr Brailsford would like to have a word

Yes, the original question invited us to ignore air resistance.

The main problem with perpetual motion machines is that greedy humans expect to be able to extract energy from them...

 

[Eric Olthwaite]

The main problem with perpetual motion machines is that greedy humans expect to be able to extract energy from them...

It is for this reason that I oppose schemes which generate electricity from the tides. I mean, we are literally stealing gravity from the moon. That can't end well.

 

[Arrowfoot]

According to TrigerBroomNometry its always the same car / broom...

Damn, you beat me to it.

 

[Julia9054]

Does a human heart ❤ have a fixed number of lifetime beats?

Dunno but those with a faster resting heart rate have a lower life expectancy even when other confounding factors have been controlled for