Question
Asked Nov 8, 2019
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The door shown in the figure is equipped with a torsional spring of stiffness 25 Nm/rad and a torsional viscous damper c so that it automatically returns to its closed position after being opened. The door has a mass of 60 kg and a centroid moment of inertia about axis AB parallel to the door's axis (Oz) of 7.2 kgm^2.

a. What is the damping coefficient such that the system is critically damped?
b. What is the initial angular velocity of the door so that the door is opened 70 degrees? How long will the door return to 5 degrees of completely closing?
c. Repeat a and b if the door is designed with a damping ratio of 1.3.
check_circle

Step 1

a.

Consider I as the moment of inertia and Zeta as the damping ratio. The damping coefficient is,

Step 2

b.

Calculate the angular velocity.

Step 3

Calculate the time taken for the...

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EngineeringMechanical Engineering