an object in equilibrium the net torque acting on it vanishes only if each torque is calculated as:

a. The center of mass
b. The center of gravity
c. The geometric center
d. The point of application of force
e. The same point

The center of mass

Something is missing in the description. Recheck it, as it is, it does not make sense.

To determine which point we should calculate the torques around in order for the net torque on an object in equilibrium to vanish, let's review the concept of torque.

Torque is a measure of the turning force or rotational effect of a force around a certain point. It depends on the magnitude of the force and the distance between the point of rotation and the line of action of the force. The equation for torque is:

Torque = Force x Lever Arm

Now, in order for an object to be in equilibrium, the net torque acting on it must be zero. This means that the clockwise torques must balance out the counterclockwise torques.

So, which point should we choose to calculate the torques around?

a. The center of mass:
The center of mass is the average position of the mass distribution of the object. Calculating torques around the center of mass is a valid approach to determine equilibrium. However, it only works for objects with uniform density and symmetric shapes.

b. The center of gravity:
The center of gravity is the point where the entire weight of an object can be considered to act. It is equivalent to the center of mass in a uniform gravitational field. So, calculating torques around the center of gravity would also work for objects in equilibrium, assuming a uniform gravitational field.

c. The geometric center:
The geometric center refers to the point that divides an object into equal parts in terms of its shape. Calculating torques around the geometric center can be a suitable choice for symmetrical objects.

d. The point of application of force:
This refers to the exact point where a force is applied on the object. Calculating torques around the point of application of force is necessary when the only force acting on the object is applied at a single point.

e. The same point:
The net torque will always be zero if all the torques are calculated around the same point. However, it's crucial to choose a point that makes the calculations simpler or allows for symmetries in the object to be exploited.

In summary, for an object in equilibrium, the net torque acting on it vanishes if the torques are calculated around any of the points mentioned (a, b, c, d, or e), as long as the calculations are done correctly. The choice of the point depends on the specific characteristics and symmetry of the object.