The free-body diagram below represents a 1500-kg car sitting on a 3000-kg bridge supported at its far ends. The car's position is three quarters of the length L from the left end of the bridge. Identify the one error in the torque equation below:
A) never produces a torque on the bridge no matter where the axis of rotation is placed.
B) never produces a torque on the bridge no matter where the axis of rotation is placed.
C) cannot produce a torque on the bridge no matter where the axis of rotation is taken since it is at the center of the bridge.
D)Because the perpendicular distance to from the left end of the bridge is 0, F1L should be 0.
E)Because the perpendicular distance to from the right end of the bridge is 0, F2L should be 0.

Question

The free-body diagram below represents a 1500-kg car sitting on a 3000-kg bridge supported at its far ends. The car's position is three quarters of the length L from the left end of the bridge. Identify the one error in the torque equation below: ​  ​  ​
A) never produces a torque on the bridge no matter where the axis of rotation is placed. 
B) never produces a torque on the bridge no matter where the axis of rotation is placed. 
C) cannot produce a torque on the bridge no matter where the axis of rotation is taken since it is at the center of the bridge. 
D)Because the perpendicular distance to from the left end of the bridge is 0, F1L should be 0. 
E)Because the perpendicular distance to from the right end of the bridge is 0, F2L should be 0.

Quizplus · Accepted Answer

The error in the torque equation is that because the perpendicular distance to F1 from the left end of the bridge is 0, F1L should be 0. Therefore, option D is correct and the other options are either irrelevant or incorrect.

The Free-Body Diagram Below Represents a 1500-Kg Car Sitting on a 3000-Kg