The point masses and and be located at and and .

(a)

Find the center of mass of the point of masses lying on the -axis to the four units right.

Moments and Center of mass: One dimensional system :

Let the point masses be located at .

1. The moment about the origin is .

2. The center of mass is  , where is the total mass of the system.

Find .

Substitute , ,  and and

,  in .

.

Total mass of the system is .

Substitute and in .

.

The center of mass is .

(b)

Find the center of mass of the point of masses lying on the -axis to the two units left.

Find .

Substitute , ,  and and

,  in .

.

Total mass of the system is .

Substitute and in .

.

The center of mass is  .

(a) The center of mass is  .

(b) The center of mass is  .