ROTATIONAL MOTION

Why do internal forces not contribute to the net torque in a system of particles?

• They are too weak
• They act only radially
• They occur in equal and opposite pairs that cancel torques
• They increase friction

What is the role of the right-hand rule in determining the direction of CP × v?

• It measures distance
• It calculates energy
• It gives the direction of the axial angular momentum component
• It determines mass

How does the choice of origin affect the value of total angular momentum?

• No effect
• It reverses direction
• It changes the position vectors, thus altering angular momentum
• It affects only mass

What is the physical implication of L_⊥ ≠ 0 in a rotating rigid body?

• It rotates faster
• It becomes lighter
• The body will exhibit wobbling or precession during rotation
• It stops rotating

Why is the unit vector k̂ used in expressing L_z = I ω k̂?

• To measure speed
• To calculate mass
• To indicate the direction of the fixed rotation axis
• To represent time