When a box is moving it experiences a frictional force of 20n to the left, or toward the mover. what force does the mover need to apply in order to keep the box moving to the right at 1 m/s?

How have the competing explanations' experiments on atoms affected the development of the atomic model?

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

Which of the following is not am example of a polymer? protein nylon kevlar concreta