It depends on what illness and what country you are in but Mayo Clinic and Johns Hopkins are good sources.
Answer: Brownion motion is the erratic random movement of microscopic particles in a fluid, as a result of continuous bombardment from molecules of the surrounding medium.
Explanation:
Brownian motion is the random movement of particles in a fluid due to their collisions with other atoms or molecules.
A firecracker before been lit has potential energy in it. It is chemical potential energy which is due to the explosives in it.When it is lit, it gets converted into heat,light and kinetic energy.
Answer:

Explanation:
Two identical bodies are sliding toward each other on a frictionless surface.
Initial speed of body 1, m₁ = 1 m/s
Initial speed of body 2, m₂ = 2 m/s
They collide and stick.
We need to find the speed of the combined mass. Let V is the speed of the combined mass.
Using the conservation of momentum.

We have, m₁ = m₂ = m

So, the speed of the combined mass is
.
Answer:
his speed is 5cm a second