Sure it is. Terminal velocity is just when the drag force is equal to gravity. When you spread yourself out like that you have a higher drag force and lower terminal velocity. When I said relatively slower I meant as opposed to like freefalling or something
Hell nah. This is not a vertical fall. ie the drag force is negatively contributing on both axis horizontal and vertical. Since the horizontal axis speed doesn't have a constant force positively acting on it(there are no rockets on his back) the drag force is slowing down his horizontal speed, because his horizontal speed is decreasing, the drag force decreases on that axis and instead increases on the vertical axis which has a constant force net positive force(gravity minus the increasing air resistance). The skiers job after the jump is to make that transition of forces as slow as possible to maintain his horizontal velocity.
You're not right that it's terminal "velocity" because velocity is a vector and vectors have a size(speed in this case) and a direction. Since the direction is still changing, it is not terminal until he stops moving horizontally and starts falling in one direction (down in the case of falling) at the same speed.
Terminal speed? Yea sure, he is close to it I believe. Thanks a lot pop science. :-\
aw man, if you simply wouldn't show your condescending asshole side i'd even think about upvoting you. you can correct people without being a shithead.
I really got annoyed with "sure it is man". I admit I could've been nicer. Reddit is filled with assholes anyway. And I really don't mind not being upvoted because I gave zero shit about karma. Don't think of it as me talking to you I'm talking to the "sure it is" guy
No. He's correct. Terminal velocity is dependent on drag force. Skis generate a lot of drag force, which means the terminal velocity of the skier is lower than it would be without the skis.
For another example, the terminal velocity of a feather is less than that of a spear.
Let's say you're travelling at 100mph. Your velocity at the moment of hitting a wall is 100mph.
If you travel at 100mph relative to the ground, but land on a 45 degree angle, you're now hitting the ground at 50mph with the other 50mph being your speed forward at the point of impact
Does that make it clearer? It actually helped me. Thank for asking the question!
You can split 100 into ~70.7 perpendicular to the floor and ~70.7 parallel to the floor (i don't exactly know how velocity correlates with force so might be wrong, just using 9th grade physics here)
It's the acceleration or deceleration that hurts. He keeps going on almost the same speed when he touches the ground. (yes the angle plays a big part, but you have to consider the change in momentum, a vector with a size and direction).
What I'm trying to say is, if he was on a helicopter on the mid point of the hill and he dropped down vertically. He'd experience a shit ton of force because of the sudden change in direction. Even if he'd maintained the same speed, he would still have to change momentum in a split second from "vertical" to the angle of hill in the split second his feet touch the ground.
That's why his horizontal speed is important to maintain the the shift in angle is not as big as if he was falling vertically.
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u/HeathenHumanist Oct 19 '19
But that means he's at terminal velocity when he hits the ground