1.

Two small wooden blocks are placed on a circular rotating table of radius 1 m at distance 10 cm and 60 cm from the centre of the table. The table is rotating with angular velocity 4 rad s-1 about its axis of rotation. Out of these two blocks which one continues to revolve with the table. Given μ = 0.2

Answer»

r = 1 m, ω = 4 rad s-1, μ = 0.2

The wooden block will continue to revolve with table if force of friction is equal to or greater than the centripetal force required by it.

i.e., F ≥ {mv2}/{r}

Since F = μR = μ mg

Hence μ mg = mv2/r or, μ mg ≥ mr ω2  (∴ v = ωr)

or mrω2 = μ mg or, r ≤ μg/ω2

or, r ≤ {0.2 x 9.8}/{16} ≤ 0.123 m

Thus, the block placed at 100 cm will revolve with the table.



Discussion

No Comment Found