The answer should be B. According to the conservation of energy, the energy cannot be created nor destroyed, but it can be transformed. Since the object is moving down, that means its height is decreasing, causing the potential energy decreasing and the kinetic energy increasing to fulfill the conservation law.
Electromagnetic waves do not require a medium to travel through. They can travel through empty space or matter.
1 newton is the force needed to accelerate 1 kilogram of mass
at the rate of 1 meter per second² .
1 N = 1 kg-m/s² .
It's a force equal to roughly 3.6 ounces.
This theory was first proposed by Nicolaus Copernicus. Copernicus was a Polish astronomer. He first published the heliocentric system in his book: De revolutionibus <span>orbium </span>coelestium<span> , "On the revolutions of the heavenly bodies," which appeared in 1543.</span>
