When an object is above the Earth's surface it has gravitational potential energy (GPE). The amount of GPE an object has depends on its mass and its height above the Earth's surface. The weight of an object is the size of the force of gravity pulling the object down. When an object falls it transfers GPE to KE (kinetic energy).
Water droplets acts as tiny prism in the sky. The sunlight when enters these tiny droplets undergo internal reflection and also refract these rays which are dispersed causing a band of seven colors called rainbow.
A huge rotating cloud of particles in space gravitate together to form an increasingly dense ball As it shrinks in size, the cloud rotates faster. Because Angular momentum is conserved, so when it shrinks the moment of inertia decreases, then angular speed must increase. So it rotates fast.
A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave. I hope I got it correct !!