Question of the day

[davy83]

How then do you explain the instant the fly is at a velocity of zero and in contact with the train? insisting this is not true defies physics as you have said?

I thought I'd explained the difference regarding energy and momentum between elastic and inelastic collisions? It's verifiable that the train does not at any time, no matter how brief and on what scale, have a velocity of zero.

 

[drewf]

Whale fart?

Sadly not...

 

[zagatoes30]

Question then:

What creates the loudest underwater sound, and how it is actually created? This happens all the time, every day - it's not an atomic explosion or similar.

The Bloop? Not an animal but something to do with Ice Melting or Ice Earthquake ?

 

[drewf]

How then do you explain the instant the fly is at a velocity of zero and in contact with the train? insisting this is not true defies physics as you have said?

Conservation of energy and momentum.

The kinetic energy that the fly has is extremely small - mass of .000001 kg, it's doing 5mph (2.24m/s) northbound, and therefore has a KE of say 0.000025 Joules.

The KE of the train is a bit higher... Say around 100tons mass, then the KE is 101250000 Joules.

The train has to overcome the KE of the fly, and reverse it's velocity vector, and accelerate it up to 100mph southbound. The energy loss to the train is imperceptible... Under standard Newtonian laws, the train CANNOT have an impulse delivered to it to bring its velocity to zero for an instant. Not unless an equal or even large impulse is delivered, and boy will that smart...

 

[drewf]

The Bloop? Not an animal but something to do with Ice Melting or Ice Earthquake ?

I've no idea what 'The Bloop' is!

Nothing to do with ice or melting ice.

 

[Chrisbassett]

If it's not whales it has to be something seismic or landscape altering...earthquakes?

 

[drewf]

Not earthquakes

 

[Chrisbassett]

If ice bloops and no one hears it, does it make a sound?

 

[daverichardson]

Crocodiles

 

[drewf]

Not crocs.

 

[BennyD]

Alligators playing the drums?

 

[daverichardson]

Fin slapping whales

 

[BennyD]

High-fiving otters?

 

[drewf]

Sadly not so...

Clue: It's not just the one animal that makes the sound.

 

[BennyD]

A big pod of whales farting in unison? Hump!ng hippos?

 

[drewf]

Nope, but apparently a Blue Whale's fart bubbles are large enough to enclose a horse.

 

[BennyD]

A dray horse or a Dartmoor pony?

 

[GeoffCapes]

I know it's not an animal, but surely a ship/submarine propeller makes a fair amount of sound underwater.

Failing that one of them Giant Squid's from the deep.

Or the Kraken!

 

[Needamaser]

A dray horse or a Dartmoor pony?

Would need to be a seahorse.

 

[BennyD]

My underwater farts would enclose a seahorse.