Some bacteria are propelled by biological motors that spin hair-like flagella. a typical bacterial motor turning at a constant angular velocity has a radius of 1.57 x 10-8 m, and a tangential speed at the rim of 2.21 x 10-5 m/s.
(a) what is the angular speed (the magnitude of the angular velocity) of this bacterial motor?
(b) how long does it take the motor to make one revolution?

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Aweight lifter raises a 1600 n barbell to a height of 2.0 meters. how much work was done? w = fd a) 30 joules b) 3000 joules c) 320 joules d) 3200 joules

Ametal ring 4.20 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. these magnets produce an initial uniform field of 1.12 t between them but are gradually pulled apart, causing this field to remain uniform but decrease steadily at 0.240 t/s . (a) what is the magnitude of the electric field induced in the ring? (b) in which direction (clockwise or counterclockwise) does the current flow as viewed by someone on the south pole of the magnet?