The Giant-Impact Hypothesis suggests that 4.5 billion years ago a Mars sized proto- planet named Theia collided with the earth ejecting enough matter into space to coalesce and form the moon. Theia was traveling 4.2 km/s and was 0.45 the mass of the earth when it collided. Assuming earth to be the inertial frame of reference, what was the resulting linear velocity of the Earth-Moon system after the collision?

Ais useful when you need a simple machine to you separate two things. a. lever b. screw c. pulley d. wedge

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 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

Describe uniform velocity and variable velocity in short