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The amusement park ride consists of a 200-kg car and passenger that are traveling at 3 m>s along a circular path having a radius of 8 m. If at t = 0, the cable OA is pulled in toward O at 0.5 m>s, determine the speed of the car when t = 4 s. Also, determine the work done to pull in the cable.

Respuesta :

Answer:

[tex]W = 724.89\ J[/tex]

Explanation:

given,

mass of the car = 200 Kg

speed = 3 m/s

radius of the circular path = 8 m

time t = 0

speed as O

Speed = 0.5 m/s

time = 4 s

work done = ?

initial angular velocity

[tex]P_1 = m v r_1[/tex]

[tex]P_1 = 200 \times 3 \times 8[/tex]

[tex]P_1 = 4800\ Kg m/s^2[/tex]

radius at 4 second

[tex]r_2 = r_1 - v_0\ t[/tex]

[tex]r_2 = 8 -4\times 0.5[/tex]

[tex]r_2 = 6\ m[/tex]

[tex]P_2 = m v_2 r_2[/tex]

[tex]P_2 = 200 \times v_2 \times6[/tex]

[tex]P_2= 1200v_2\ Kg m/s^2[/tex]

now,

[tex]1200v_2= 4800\ Kg m/s^2[/tex]

v₂ = 4 m/s

[tex]v' = \sqrt{4^2 + 0.5^2}[/tex]

v' = 4.031 m/s

work done

[tex]W = \dfrac{1}{2}m(v_f^2 - v^2)[/tex]

[tex]W = \dfrac{1}{2}\times 200 \times (4.031^2 - 3^2)[/tex]

[tex]W = 724.89\ J[/tex]