Answer:

Explanation:
k = Coulomb constant = 
v = Velocity of electron = 
q = Charge of electron = 
m = Mass of electron = 
r = Radius
The electrical and centripetal force will balance each other

The radius of the orbital is 
Answer:Visible light is a small part of the electromagnetic spectrum. The spectrum covers everything from gamma rays, x-rays, visible light, infrared, microwave and radio waves. Each part of the spectrum, including the different colors of visible light, have different wavelengths (the space between each wave).
Explanation:
Where's the diagram for question 1?
Reactions occur when two or more molecules interact and the molecules change. Bonds between atoms are broken and created to form new molecules. That's it.
Answer:
Push and pull both are forces , but the difference is in their direction at which it is applied . If the force applied in the direction of motion of the particle then we call it as push . If that force applied in the direction OPPOSITE to the motion of particle then it is termed as pull