Question

A disc rotating about its axis with angular speed ω₀ is placed lightly (without any translation push) on a perfectly frictionless table. The radius of the disc is R. What are the linear velocities of the points A, B and C on the dise shown in the fig.? will the disc roll in the direction indicated?

Answer 1

Using the relation v = rω.

For point A, v_A = Rω₀ in the direction of arrow.

For point B, v_B = Rω₀ in the opposite direction of arrow.

For point C, v_c = Rω₀/2 in the direction of arrow. The disc will not roll in the given direction because friction is necessary for the rolling motion.