An object is dropped from the top of a tall building. at 2 seconds, it is 64 feet from the top of the building. at 4 seconds, it is 256 feet from the top of the building. what is the average rate the object was traveling in the interval between 2 and 4 seconds?
d. machines can never create energy, they just convert it. remember the law of conservation of matter. it cannot be created or destroyed.
i would think by taking all the water out and storing it somewhere else and filtering it or cleaning it then put it back
correct answer is positive force → balanced force → negative force
when diego gives a big lift to the piano with the of pulley system that time, initially piano moves upward so positive force acts on it.
later, piano stops, in this condition balanced force act on it since force applied by diego is balanced by gravitational force of earth.
after some time piano starts falling in this condition negative force will act on the piano. in this condition, gravitational force will acts on piano in downward direction.