A disk has a radius of 30 cm and a mass of 0.3 kg and is turning at 3.0 rev/s. A trickle of sand falls onto the disk at a distance of 20 cm from the center and build a 20cm radius ring of sand on it. How much sand must fall on the disk to decrease the speed to 2.0 rev/s? Idisk = 1 2mR2 ; Iring = mR

The mass of the sand that will fall on the disk to decrease the is 0.3375 kg

Explanation:

Moment before = Moment after

where;

I is moment of inertia = Mr² = 0.3 x (0.3)² = 0.027 kg.m²

substitute this in the above equation;

Therefore, the mass of the sand that will fall on the disk to decrease the is 0.3375 kg

depends on what you mean by "group." for order, it would be coleoptera (beetles). for class, it would be insecta (insects). for phylum, it would be the arthropoda (animals with jointed exoskeletons).

explanation: