You decided to take a break from college and go hiking in the wilderness of Canada. With yearly snowfalls in excess of 120 cm near Edmonton, Alberta, you find it necessary to purchase a pair of snow shoes. After a trip to the local sporting goods store, you realize that any commercial pair is out of your price range. Making them would be significantly cheaper. If you wanted to only compress snow 1 cm while standing, what would the area of each snow shoe have to be? (Approximate the snow as a spring system with a spring constant per unit area of 1.96×105 N/m3 and estimate your mass.)

Once your snow shoes are made, you finally travel to the trails. You walk up and orient yourself perpen- dicular to a stream, observing that it is flowing at 1 m/s. Something catches your eye and you look up at a 45? angle from the horizontal. You spot a weasel climbing a tree branch over a stream. In this -20?C winter weather, trees are not as flexible and snap when put under too much stress. This particular weasel is a little too heavy for the tree limb, causing it to brake, sending the poor woodland creature falling into the water directly in front of you. You hear the crack of the tree 22 ms after you see it start to fall. How fast is the weasel moving when it hits the water?

The weasel starts drifting towards a waterfall. Luckily a beaver dam (2 m wide) is 10 m downstream from where you are standing (P). You can only run at a top speed of 2 m/s in the homemade snow shoes. If the cross-sectional area of the stream decreases by factor of 10× while passing through the dam, can you catch and save the weasel before it moves past the dam (X), down the waterfall?