ROTATIONAL MOTION

What happens to the centre of mass when a particle is moved along a line parallel to the x-axis?

• All coordinates change
• Only the X-coordinate may change
• It remains fixed
• It shifts vertically

In a system of three particles not in a straight line, what defines the plane in which the centre of mass lies?

• The horizontal plane
• The plane containing all three particles
• The vertical plane
• A perpendicular plane

How is the X-coordinate of the centre of mass affected if all particle masses are doubled?

• It doubles
• It halves
• It remains unchanged
• It becomes zero

What is the primary purpose of defining the centre of mass for a system of particles?

• To calculate total kinetic energy
• To determine the size of the system
• To simplify the analysis of motion of the system
• To find the gravitational force

What is the centre of mass of a system of particles if all particles are on the y-axis?

• It is at the origin
• It lies on the y-axis
• It is at infinity
• It has no defined position