I went to see a ski jump competition last weekend (Puijo hill, Kuopio). One of the competitors is a relative who will start studying physics at a local university in this fall. I watched how the jumpers leaned backwards while slowing down uphill. Take a look here (last seconds of thevideo while sliding across the grass):
<https://www.youtube.com/watch?v=rV1521q7rLc>
We had a nice chat on why they lean backwards and what is the physics explaining this. The reason is that without leaning backwards they would be prone to fall while going uphill. The physics can be understood in terms of torques; this soon-a-freshman-physicist worked it out quite quickly.
It occured to me that this would make a nice real-life conceptual question on forces and torques. Any other questions you might ask students to explain regarding the jump?
Best wishes,
Antti Savinainen,PhD
Kuopio Lyseo High School
Finland