In: Chemistry
Is it true that molecules always rotate about their center? Explain.
The principles associated with molecular rotation, the case of an object of mass m rotating around a fixed center will be considered. In this case, it is simpler to consider the center of the rotation as being stationary, but this is only for convenience. The moment of inertia, I, in this case, can be represented as I = mr2. The center of rotation is a point that’s the same distance from any pair of corresponding points.
The center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may be applied to cause a linear acceleration without an angular acceleration.
If the center of the molecule is not the center of mass i.e any other point then it will not rotate via center of the molecule.
If the center of the molecule is the center of mass i.e any other point then it will rotate via center of the molecule.
So. it is not always true that molecules always rotate about their center but maximam cases it does.