For a body rotating at constant angular velocity omega, the linear speed at distance r from the axis is v = omega × r. Two points at radii 0.1 m and 0.4 m on the same rotating disc have linear speeds in ratio:
A1:4
B1:1
C4:1
D1:2
Answer & Solution
Correct answer: A. 1:4
v1/v2 = (omega × 0.1) / (omega × 0.4) = 1/4. So speeds in ratio 1:4. Same omega throughout, but linear speed grows with r.
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