The force of the water hitting the pipe constantly is enough.
Air in the system
The amount of vibration of the individual molecules (H2O) in the water determines its temperature.
The vibration and loud noise in your hot water pipes when turned on is likely caused by water hammer. This occurs when the flow of water is suddenly stopped or redirected, causing a shockwave that reverberates through the pipes. Installing water hammer arrestors or adjusting water pressure can help reduce or eliminate this issue.
Water sputters when first turned on because air trapped in the pipes is being pushed out by the flowing water. This causes the water to come out in bursts or spurts until the air is fully expelled from the system.
choir members in your pipes
An increase in the temperature of gas causes an increase in volume. At the center of a popcorn kernel there is a small pocket filled with water. When the microwave is turned on it releases microwaves which rapidly vibrate the water molecules in the center of the kernel. This rapid vibration causes the water in the center of the kernal to heat up and thus expand. When the pressure is too great to be containd the kernal explodeds and "pops".
Pipes rattle when water is turned off due to a phenomenon called water hammer. This happens when the sudden stop of water flow creates a pressure surge that causes the pipes to vibrate and make noise.
If water gets under a faucet washer it can cause a loud vibration when the water is turned on. You either need to find a proper replacment or get a new faucet.
It's called water-hammer. I vibration from the water pressure. A snub-end pipe can be added to devert the vibration.
Lose washer / excessive velocity (FPS)
The particles gain energy (kinetic energy) and begin to vibrate. This vibration causes heat. As the particle vibrates, it will collide with other particles in water and pass this energy on to neighbouring particles which causes the heat conduction.
Waves that travel through a medium are caused by vibration eg sound waves are caused by vibrating drum/ vocal cords etc and this causes the air particles to vibrate; a vibration in a still pond will cause waves of water. However, light, radio waves are radiation. Electromagnetic waves are radiated eg light from the Sun is radiated to Earth through the vacuum of space.
vibration