ROTATIONAL MOTION

If a system has zero total mass, what happens to the centre of mass formula?

• It becomes zero
• It becomes infinite
• It becomes undefined
• It remains same

What is the significance of the centre of mass in rotational motion?

• Rotation never occurs about it
• It is the point about which pure rotation occurs if no translation
• It is always fixed
• It has maximum kinetic energy

How is the Y-coordinate of centre of mass affected if all yi are multiplied by 2?

• Y remains same
• Y halves
• Y doubles
• Y becomes zero

For a system of four particles of equal mass at the corners of a square, where is the centre of mass?

• At one corner
• At the centre of the square
• At the midpoint of a side
• Outside the square

What is the centre of mass of two particles of mass m each at positions x and -x?

• At x
• At -x
• At the origin
• At x/2