Question

In a metre rod , half of it is made of copper and rest half of steel . Weight of copper and

steel are 9 N and 8 N respectively . Is the center of gravity of rod is at its geometric

center ? If not where is it.​

Answer 1

Given: In a metre rod , half of it is made of copper and rest half of steel

To find: Is the center of gravity of rod is at its geometric  center ?

Solution:

• Now we have given that half of it is made of copper and rest half of steel . Weight of copper and  steel are 9 N and 8 N respectively .

• L/2 is geometric center.

• Center of Mass of steel part will be at 3L/4 and of copper will be at L/4

• So,

                    Center of Mass = m1y1 + m2y2 / m1 + m2

                    Center of Mass = 9n(L/4) + 8n(3L/4) / 9n + 8n

                    Center of Mass = 9nL + 24nL / 4 / 17n

                    Center of Mass = 33L / 68

                    Center of Mass = 0.4852 L

Answer:

              So the center of gravity of rod is not at its geometric  center but at the distance of 0.4852 L from bottom.