Projectile Motion Homework: Plane Speed, Decoy Release & Displacement Equations

AI Thread Summary
The discussion revolves around solving a projectile motion problem involving an airplane releasing a radar decoy. The plane's speed is 180 mi/h at a 30-degree angle, and the decoy lands 2300 ft away. The user converted units and calculated the horizontal and vertical velocities but struggled to determine the height of the plane and the time the decoy was in the air. They provided answers of 1657.67 m for height and 22.95 seconds for time but expressed uncertainty about their correctness. Additional guidance was offered on using horizontal speed to find the dropping time and clarifying the second problem regarding a sprinter's acceleration.
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Homework Statement


a certain airplane has a speed of 180 mi/h and is diving at an angle of 30.0 degrees below the horizontal when a radar decoy is released. The horizontal distance between the release point and the point where the decoy strikes the ground is 2300 ft. (a) How high was the plane when the decoy was released? (b) how long was the decoy in the air?


Homework Equations


Displacement equations


The Attempt at a Solution



I tried converting every distance unit to meters and got the velocity was 80.45 m/s
and the horizontal vel = 69.67 m/s
vertical vel = 40.225 m/s

but then I had to find part b before I could answer part a?

p.s. the answers I got were a) 1657.67m and b) 22.95 sec.

i don't think this is right
 
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oh and 2nd problem

a) What is the acceleration of a sprinter running at 10 m/s when rounding a bend with a turn radius of 25m? b)In what direction does the acceleration vector point?

I got a), it's 4 m/s2. But what does b) asking?
 
Your velocity components seems to be correct, but your dropping distance not.

Show us how you calculated a) with the substituted values. Hint: Use the horizontal speed to calculate the dropping time.
 
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