In our Inbox:

In our Inbox:

My 13-year-old son just said, “Mum, I think I have a good idea. The people in America protesting ICE should call themselves LAVA — Local And Very Angry. And lava melts ice. You should post that and see if it's a good idea"

We’re about as far away from the United States as you can get, here in Perth, Western Australia. But I hope the people over there know that even a young boy on the other side of the world can see when something isn’t right.

Emily, Perth

@NO_KINGS_muc Sadly Lava has a specific heat capacity of <1kJ/kgK, while Ice has slightly above 2kJ/kgK, a specific melting energy of 334kJ/kg, Water then has a specific heat capacity of over 4kJ/kgK, and a specific vapourizing energy of about 2200kJ/kg.

Since hot lava is not just going to melt ice on contact, but vapourize the water: Suppose you've got 1kg of 1200°C lava. This thus has an energy of less than 1500kJ.

Suppose you've got ice at -20°C. Then for each kg of ice you'll need over 20*2+334=374kJ to melt. So theoretically we could melt 3–4kg of ice. But since until say 200°C the molten water is going to evaporate pretty fast this means for ~1000kJ you need to also heat the water to 100°C (420kJ/kg) and vapourize it (2.2MJ/kg).

So all in all you'd have ~3MJ/kg of ice. So this 1000kJ can evaporate only ⅓kg of ice. The remainig 200kJ to 0°C will maybe rather melt the ice, but at this point you have only energy for melting a bit more than ½kg of ice. So all in all 1kg of 1200°C lava will only melt ~1kg of ice at -20°C.

So don't think this would be overly effective.

In our Inbox:

My 13-year-old son just said, “Mum, I think I have a good idea. The people in America protesting ICE should call themselves LAVA — Local And Very Angry. And lava melts ice. You should post that and see if it's a good idea"

We’re about as far away from the United States as you can get, here in Perth, Western Australia. But I hope the people over there know that even a young boy on the other side of the world can see when something isn’t right.

Emily, Perth

@NO_KINGS_muc Sadly Lava has a specific heat capacity of <1kJ/kgK, while Ice has slightly above 2kJ/kgK, a specific melting energy of 334kJ/kg, Water then has a specific heat capacity of over 4kJ/kgK, and a specific vapourizing energy of about 2200kJ/kg.

Since hot lava is not just going to melt ice on contact, but vapourize the water: Suppose you've got 1kg of 1200°C lava. This thus has an energy of less than 1500kJ.

Suppose you've got ice at -20°C. Then for each kg of ice you'll need over 20*2+334=374kJ to melt. So theoretically we could melt 3–4kg of ice. But since until say 200°C the molten water is going to evaporate pretty fast this means for ~1000kJ you need to also heat the water to 100°C (420kJ/kg) and vapourize it (2.2MJ/kg).

So all in all you'd have ~3MJ/kg of ice. So this 1000kJ can evaporate only ⅓kg of ice. The remainig 200kJ to 0°C will maybe rather melt the ice, but at this point you have only energy for melting a bit more than ½kg of ice. So all in all 1kg of 1200°C lava will only melt ~1kg of ice at -20°C.

So don't think this would be overly effective.

@lazy @NO_KINGS_muc
So as long as LAVA outnumber ICE by more than 2:1, victory for LAVA ??

No problem!

( my brain isnt quite right ATM so I might have read that totally wrong!)

In our Inbox:

My 13-year-old son just said, “Mum, I think I have a good idea. The people in America protesting ICE should call themselves LAVA — Local And Very Angry. And lava melts ice. You should post that and see if it's a good idea"

We’re about as far away from the United States as you can get, here in Perth, Western Australia. But I hope the people over there know that even a young boy on the other side of the world can see when something isn’t right.

Emily, Perth

@OliverNoble Looks like it might require at least 3:1, though I admit I'm not mathing well today. Still, I think we have those numbers, easily.

@wesdym
But are we counting by weight or by volume? (And I think it's a Great slogan, it's a political statement, not high school physics coursework)
@OliverNoble

In our Inbox:

My 13-year-old son just said, “Mum, I think I have a good idea. The people in America protesting ICE should call themselves LAVA — Local And Very Angry. And lava melts ice. You should post that and see if it's a good idea"

We’re about as far away from the United States as you can get, here in Perth, Western Australia. But I hope the people over there know that even a young boy on the other side of the world can see when something isn’t right.

Emily, Perth

In our Inbox:

My 13-year-old son just said, “Mum, I think I have a good idea. The people in America protesting ICE should call themselves LAVA — Local And Very Angry. And lava melts ice. You should post that and see if it's a good idea"

We’re about as far away from the United States as you can get, here in Perth, Western Australia. But I hope the people over there know that even a young boy on the other side of the world can see when something isn’t right.

Emily, Perth

@NO_KINGS_muc Sadly Lava has a specific heat capacity of <1kJ/kgK, while Ice has slightly above 2kJ/kgK, a specific melting energy of 334kJ/kg, Water then has a specific heat capacity of over 4kJ/kgK, and a specific vapourizing energy of about 2200kJ/kg.

Since hot lava is not just going to melt ice on contact, but vapourize the water: Suppose you've got 1kg of 1200°C lava. This thus has an energy of less than 1500kJ.

Suppose you've got ice at -20°C. Then for each kg of ice you'll need over 20*2+334=374kJ to melt. So theoretically we could melt 3–4kg of ice. But since until say 200°C the molten water is going to evaporate pretty fast this means for ~1000kJ you need to also heat the water to 100°C (420kJ/kg) and vapourize it (2.2MJ/kg).

So all in all you'd have ~3MJ/kg of ice. So this 1000kJ can evaporate only ⅓kg of ice. The remainig 200kJ to 0°C will maybe rather melt the ice, but at this point you have only energy for melting a bit more than ½kg of ice. So all in all 1kg of 1200°C lava will only melt ~1kg of ice at -20°C.

So don't think this would be overly effective.

@lazy
@NO_KINGS_muc
Good thing that there is like 100 times more LAVA than ICE.

LAVA does not fight alone. Once the vulcano erupts, LAVA will reform the very land!