Calculate the efficiency of a four wheeled Pulley system if it is used to lift a load of 500N by using an effort of 300N

When many atoms are split in a chain reaction, a large explosion occurs. this is an example of what type of energy conservation

Which statement best describes how private industry decides where to spend the money on research and development

Ajet plane has a sound level of 120 db at a distance of 60 m. what is the q23. sound level at a distance of 6.0 km? (60)2 (6000)? om solution 80db db, hint: 16x assume ultrasound waves travel through the body of an animal at 1540 q24. m/s. if a 30,000 hz signal were reflected off a portion of a heart which was moving toward the source at 3 m/s, what frequency signal would return to the stationary source? solution 30.117hz