An irregularly shaped object that is 10 m long is placed with each end on a scale.If the scale on the right reads
While the scale on the left reads
How far from the left end is the center of gravity of this object?
A)5.7 m
B)7.4 m
C)4.3 m
D)14 m

Question

An irregularly shaped object that is 10 m long is placed with each end on a scale.If the scale on the right reads 
While the scale on the left reads 
How far from the left end is the center of gravity of this object?
A)5.7 m 
B)7.4 m 
C)4.3 m 
D)14 m

Quizplus · Accepted Answer

We can use the concept of torque here. The torque due to the weight of the object on the left scale is equal and opposite to the torque due to the weight of the object on the right scale. Let's assume that the distance of the center of gravity (CG) from the left end is x. Then, the torque due to the weight on the left scale is (10-x) times the weight of the object, and the torque due to the weight on the right scale is x times the weight of the object.

We can equate these torques to get:

(10-x) x (weight of object) = x x (weight of object)
Simplifying, we get: 
10-x = x 
2x = 10 
x = 5

Therefore, the center of gravity is 5 m from the left end.

An Irregularly Shaped Object That Is 10 M Long Is