Determine a prescalar, ocr0a value, and isr for an 8-bit timer to generate a 400hz square wave for 3 seconds on pd1. recall the arduino runs at 16 mhz and valid prescalars are: 1, 8, 64, 256, 1024(choose the smallest prescalar that works).

What is the measurement of how fast an object moves relative to a reference point?

What is friction? how does it affect the motion of an object?

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.