Chapter 8, Problem 63A

To determine

To Rank:The torques on the five doors from least to greatest.

Explanation of Solution

Introduction:

Torque depends on the magnitude of applied force,angle between force and the radius from the axis of rotation and distance from the point where force applied to the axis of rotation.

For door E, the force applied parallel so torque is zero.

For door D, the force applied near the axis of the door so the torque is zero.

For door C, the force applied at middle of the door with making some angle with the door.

For door B, the force applied perpendicular and at center of the door.

For door A, the force applied at other end of the door so torque will be high.That is greatest torque produced when force is appliedaway from the door hinge and at an angle perpendicular to the door.

Conclusion:

So, ranking from least to greatest of door is E, D, C, B and A.