Calculating Hawk's Shadow Speed

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The discussion revolves around calculating the speed of a hawk's shadow as it dives at a constant velocity of 5.00 m/s at a 60-degree angle below the horizontal. Participants clarify that the shadow's speed can be determined using the horizontal component of the hawk's velocity, which can be calculated using trigonometric functions. The calculations confirm that the shadow moves at 2.5 m/s, whether approached through the cosine of 300 degrees or by visualizing a 30-60-90 triangle. Additionally, there is a request for clarification on the visual representation of the scenario, particularly regarding the shadow's position relative to the hawk's dive. The conversation emphasizes understanding the geometry involved in the problem.
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3. When the Sun is directly overhead, a hawk dives toward the ground with a constant velocity of 5.00 m/s at 60.0 degrees below the horizontal. Calculate the speed of her shadow on the level ground.

I am having some trouble picturing this problem in terms of a coordinate grid (this is in a chapter dealing with motion in two dimensions). I'm basically making a triangle, and I know (or at least I'm hoping) that the shadow is the horizontal component of the vector that is the hawk's flight. If it's 60 degrees below the "horizontal" or, the way I see it, the "line of sight", the direction is equivalent to 300 degrees if making an imaginary coordinate grid at the point before she descends, making the h.c. = 5.00cos300. Or, actually, the entire thing is a 30-60-90 triangle, so the velocity of her shadow is 2.5 m/s.

...is that right? Or, rather, is my long-winded train of thought correct?
 
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Your answer is correct. Good Job!

You should get the same answer if you did the problem with the cosine of 300 degrees or with the 30-60-90 triangle. Both descriptions of the situation can accurately be used to find the answer.

Also, your thinking, as far as I understand it, is correct. 60 degrees below the horizontal in the can be described by an angle of 300 degrees. Was this all you were asking or is there more to your train of thought that you were unsure about?
 
Last edited:
Yes you are right
 
Thank you! :DDD

That was all I was wondering.
 
Yep, yep!

Thanks a bunch! =]
 
ok can someone please explain how the picture looks for this question!
i don't understand the picture since it says the hawk is diving down under the horizontal
so where is the shadow?
help please
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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