Odd projectile motion question.

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letsfailsafe
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Homework Statement


Question: "The time of flight of the lure through the air is 3.4 seconds. (g= 9.8m/s/s)
Calculate the maximum height of the lure in its projectile motion."


Homework Equations


Not sure if I need to use this:
d = (u)(t) + (1/2)(a)(t^2)


The Attempt at a Solution



I don't know how this really works...

I'm guess to half the time (3.4/2). Thats the time when the object is at rest for a very short time (initial velocity would be 0). And use that equation on to solve the d.
 
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Once the object is at rest (top of the trajectory) what follows (on the vertical axis) is just a free fall, isn't it?
 
You could start by finding the initial vertical component of velocity and using another kinematic relation to find the height. Or do as Borek suggested.
 
So...

d = (0)(1.6) + (1/2)(9.8)(1.6)^2

= 12.544 m

Is it right?
 
The time of flight of the lure through the air is 3.4 seconds means the lure left the Earth at t=0 and landed back to Earth at 3.4sec.

So vertically the final position is back to where it started.
Y position is a horizontal line parallel to x-axis.
 
letsfailsafe said:
So...

d = (0)(1.6) + (1/2)(9.8)(1.6)^2

= 12.544 m

Is it right?
Right idea, but 3.4/2 ≠ 1.6. :wink: