CENTRE OF MASS

Every object has a point through which its weight acts. That point is called Center of Mass or Center of Gravity.

EXPERIMENT: Finding the center of mass.1. Set up the apparatus as shown in the diagram below.2. Hang the card from one of its holes and allow it to freely

swing.3. When the card comes to rest, draw a line on the card along

the string.4. Hang the card from a different hole and repeat step 2. and

3.5. Repeat step 4. once.6. The 3 lines meet at a point. This point is the Center of

mass of the card.

The card can be suspended from its center of mass and balance properly without tipping over.

STABILITY

The center of mass determines the stability of an object.

The lower the center of mass, the more stable the object is.

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States of equilibrium

There are 3 states of equilibrium:

1. Stable equilibrium:

2. Unstable equilibrium

3. Neutral equilibrium

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