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The small washer is sliding down the cord OA. When it is at the midpoint, its speed is 28 m>s and its acceleration is 7 m>s2. Express the velocity and acceleration of the washer at this point in terms of its cylindrical components.

User Nadu
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1 Answer

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Answer:

Velocity components

V_r = -16.28 m/s

V_z = -22.8 m/s

V_q = 0 m/s

Acceleration components

a_r = -4.07 m/s^2

a_z = -5.70 m/s^2

a_q = 0 m/s^2

Step-by-step explanation:

Given:

- The diagram missing is attached.

- The speed of the washer v_o = 28 m/s

- The acceleration of washer a_o = 7 m/s^2

Find:

Express the velocity and acceleration of the washer at this point in terms of its cylindrical components.

Solution:

- From figure, compute the radial position r of washer in x-y plane:

r = sqrt ( 300^2 + 400^2 )

r = 500 mm

- From figure, compute the Length L of along the OA direction:

L = sqrt ( 500^2 + 700^2 )

r = 860 mm

- The radial and vertical components of velocity are:

V_r = V_o*cos(Q)

V_z = V_o*sin(Q)

Where, Q is the angle between OA and vector r.

V_r = 28*r/L = 28*500 / 860

V_r = -16.28 m/s

V_z = 28*700/L = 28*700 / 860

V_z = -22.8 m/s

V_q = 0 m/s

- The radial and vertical components of acceleration are:

a_r = a_o*cos(Q)

a_z = a_o*sin(Q)

Where, Q is the angle between OA and vector r.

a_r = 7*r/L = 7*500 / 860

a_r = -4.07 m/s^2

a_z = 7*700/L = 7*700 / 860

a_z = -5.70 m/s^2

a_q = 0 m/s^2

The small washer is sliding down the cord OA. When it is at the midpoint, its speed-example-1
User Paul Van Jaarsveld
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4.6k points