How tough is ice?

[ssveter]

I am building a super that has the create ice power. My concept is that she can create walls of ice, hollow spheres of ice, and maybe even an ice bridge or a raft.

So it brings up the question. How much HP and DR does ice have per inch of thickness?

[the_matrix_walker]

I don't think I've seen it in a 4th Ed book. In GURPS Supers 3rd Ed however, it's on the sidebar of page 85.

DR 3 / inch for the first foot,
DR 4 / inch for the second foot,
DR 5 / inch for the third, etc until it caps out at DR 20 / Inch.

"When a wall of ice takes damage, 2/3 of the the damage (round up), is applied to reducing the DR of the remainder (in that spot). the rest reduces hit points"

It also mentions the useful...

A square foot of ice 1 inch thick weighs 4.8 lbs, and a gallon of water weighs 8.3 lbs.

[Purple Haze]

Originally Posted by the_matrix_walker

It also mentions the useful...

A square foot of ice 1 inch thick weighs 4.8 lbs, and a gallon of water weighs 8.3 lbs.

I've seen this before but I don't get it.

One imperial gallon weighs ten pounds. That makes sense, 160 fluids onces weigh 160 ounces avoirdupois.

So how does one US gallon at (128 fluid ounces) come out to 8.3 pounds?

[Bruno]

Originally Posted by Purple Haze

I've seen this before but I don't get it.

One imperial gallon weighs ten pounds. That makes sense, 160 fluids onces weigh 160 ounces avoirdupois.

So how does one US gallon at (128 fluid ounces) come out to 8.3 pounds?

the imperial gallon (≈ 4.546L) = 4.546kg of water = 10.022214 pounds
the United States (liquid) gallon (≈ 3.79 L) = 3.79kg of water = 8.35552 pounds.

It certainly seems to come out at 8.3 pounds.

I think your problem is assuming the fluid ounces are the same unit. They're not the same size.

[Purple Haze]

Originally Posted by Bruno

I think your problem is assuming the fluid ounces are the same unit. They're not the same size.

Bingo! Never occured to me. The perversity of the US never ceases to amaze.

[Bruno]

Originally Posted by Purple Haze

Bingo! Never occured to me. The perversity of the US never ceases to amaze.

Oh, that's not something special to the US measurement system. And in this case it's actually the UK you should blame - they decided to change the size of their ounce one day, not the US. But the current situation (Three different legacy systems sharing the same or similar unit names - don't forget Troy weights :P) is much better than it used to be. Each country used to have its own standard.

[Anthony]

Spaceships has statistics for ice armor; per module it has 1/5 the DR of steel armor, but that's really per unit weight, and ice is around 1/10 the density of steel, so it works out to DR 1-2 per inch. Some very old references about pyrkete claims 36 cm penetration for a 7.69mm (unclear exactly what bullet this is); if we assume that's a 7d rifle, it works out to DR 0.68 per mm or 1.73 per inch.

[Rhoanna]

Originally Posted by Purple Haze

Bingo! Never occured to me. The perversity of the US never ceases to amaze.

This is more the perversity of non-metric systems. The US went with the wine gallon, while Britain (in 1824) went with something close to the ale gallon. (There was also a corn gallon, for dry measures, and apparently a coal gallon.)

Of course, if you mean the perversity of the US still not using metric... then I quite agree with you.

[Purple Haze]

Originally Posted by Anthony

Some very old references about pyrkete claims 36 cm penetration for a 7.69mm (unclear exactly what bullet this is);

In context it can only be a .303 British (7.7×56mmR if you will).

[ClayDowling]

Originally Posted by Purple Haze

In context it can only be a .303 British (7.7×56mmR if you will).

Also known as the personal canon. It's physically painful to shoot one in an enclosed shooting box, and you can always tell when somebody has them at the range. Don't notice the noise when I'm shooting it, but I was at another part of the range one day and somebody was shooting one. About the loudest thing I'd heard out there, and I was on the skeet range at the time.