Calculate Speed of Hawk's Shadow on Ground

AI Thread Summary
To calculate the speed of a hawk's shadow on the ground when diving at 4.15 m/s at 54.5° below the horizontal, the correct approach involves using trigonometric functions to resolve the velocity into horizontal and vertical components. The calculations initially led to confusion due to the use of radians instead of degrees in the calculator. After correcting this, the user successfully found the right answer. The discussion emphasizes the importance of ensuring the calculator is set to the correct mode during such calculations. Overall, the thread highlights common pitfalls in physics problems and the value of peer assistance.
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When the Sun is directly overhead, a hawk dives toward the ground with a constant velocity of 4.15 m/s at 54.5° below the horizontal. Calculate the speed of her shadow on the level ground.

Homework Statement


Homework Equations



vxi=vicosθ vyi=visinθ (i think)

The Attempt at a Solution


360-54.5=305.5
4.15cos305.5=-2.99i
4.15sin305.5=-2.88j
then get the modulus of the vector for the speed. Gave me 4.155
Its wrong though?
Help?
Tell me where I went wrong and where to begin
Thanks
 
Last edited:
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Where is the original question?
 


Ericv_91 said:
Where is the original question?

oops sorry!
 


Is your calculator in radians or degrees?
 


ericv_91 said:
is your calculator in radians or degrees?

it was on radians! Thank you! I got the right answer!
 


Careful Careful... Make sure you never forget this during a test!
 
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