Killer Snowballs | Science of Stupid

Welcome to the Science of Stupid Christmas Grotto! As you can see, we have spared literally no expense with the decorations. But what would really make my Christmas would be to wake up on the big day to a fresh dusting of snow. Nothing beats that gentle caress of snowflakes on your face.

Yeah, in the right conditions, that soft fluffy stuff that falls from the sky feels more like concrete. But what if we stick to rolling our snowballs? Much more pleasant, right?

Okay, I think we'd better see some science. Roll a snowball down a hill, and it gains mass as it picks up snow, which compacts as it rolls, making it denser. The more mass or speed the snowball has, the more momentum it'll have. If the snowball hits someone, it'll transfer some momentum to them as it loses momentum. Sorry, but it's the law of conservation of momentum.

Now, before we start rolling, there is something else you should know about density. Freshly fallen snow is soft and fluffy, but if it melts and refreezes, some of it turns to ice, which is just 8% less dense than water and just as heavy, but rather more solid.

So, you've got a mound full of snow. Now for momentum: find yourself a nice slope and roll away. But please be careful! Believe it or not, rolling one-ton snowballs can be very dangerous. See what I mean? More mass equals more momentum.

Now that one appears to have a lot less momentum, but it's increasing to about the same as a motorbike doing 22 mph. Mhmm!