A typical small rescue helicopter has four blades, each is 4.00 m long and has a mass of 50.0 kg. The blades can be approximated as thin rods that rotate about one end of an axis perpendicular to their length. The helicopter has a total loaded mass of 1000 kg (including the four blades). (a) Calculate the rotational kinetic energy in the blades as they rotate at 300 rev/min.

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 11.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.80 m/s; (b) he is then lifted at the constant speed of 4.80 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 78.0 kg rescue by the force lifting him during each stage

An object's buoyant force and weight mean the same thing. a. trueb. false

How many meters will a car travel if its speed is 45 m/s in an interval of 11 seconds? question 2 options: a) 450 meters b) 495 meters c) 4.09 meters d) 498 meters