A wind farm generator uses a two-bladed propeller mounted on a pylon at a height of20 m. The length of each propeller blade is 12 m. A small piece from the tip of thepropeller breaks off the top propeller when the propeller is vertical. At that instant,the angular speed of the propeller is 5.2 rad/s.The fragment flies off horizontally, falls with negligible air resistance, and strikes theground at pointP. How far is pointPfrom the base of the pylon

Respuesta :

Answer:

159.37 m

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

g = Acceleration due to gravity = 9.81 m/s² = a

r = Radius = 12 m

Time taken to fall

[tex]s=ut+\frac{1}{2}at^2\\\Rightarrow 0.809=0t+\frac{1}{2}\times 9.81\times t^2\\\Rightarrow t=\sqrt{\frac{(20+12)\times 2}{9.81}}\\\Rightarrow t=2.554\ s[/tex]

Speed is given by

[tex]v=r\omega\\\Rightarrow v=12\times 5.2\\\Rightarrow v=62.4\ m/s[/tex]

Distance is given by

[tex]s=vt\\\Rightarrow s=62.4\times 2.554\\\Rightarrow s=159.37\ m[/tex]

The point P is 159.37 m from the base.

The projectile motion allows to find the result for the fall distance is:

  • The fall distance is: x = 132.3 m

Given parameters.

  • System height h = m
  • Helix length l= 12 m
  • Angular velocity w= 5.2 rad/s.

To find.

  • The fall distance.

Projectile motion.

Projectile launch is an application of kinematics to motion in two dimensions, where on the x-axis there is no acceleration and on the y-axis the acceleration is the acceleration of gravity.

Let's look for the time that the body takes to reach the ground, since the body leaves horizontally, its initial vertical speed is zero.

            y = y₉ + [tex]v_{oy}[/tex]  t – ½ g t²

The height of the body when it reaches the ground is zero.

           y= 0.

The initial height from where the body leaves is i = h+ l

            y₀ = 20+ 12= 22m

           

we substitute

            0 = y₀ + 0 – ½ g t²

            t = [tex]\sqrt{\frac{2y_o}{g} } [/tex]

Let's calculate.

          t= [tex]\sqrt{ \frac{2\ 22.0 }{9.8} }[/tex]

          t = 2.12s

Linear and angular velocity are related.

          v= rw

          v= 12 5.2

          v= 62.4 m/s

On the x-axis there is no acceleration so we can use the uniform motion relationship.

           x= vt

Let's calculate.

           x= 62.4  2.12

           x = 132.3m

In conclusion using projectile motion we can find the result for the fall distance is:

  • The fall distance is: x = 132.3 m

Learn more about parabolic motion here: brainly.com/question/24216590