B. Maximal lightheadedness
Answer: v = 
Explanation: q = magnitude of electronic charge = 
mass of an electronic charge =
V= potential difference = 4V
v = velocity of electron
by using the work- energy theorem which states that the kinetic energy of the the electron must equal the work done use in accelerating the electron.
kinetic energy =
, potential energy = qV
hence, 

Answer:
When it's closest to the sun.
Explanation:
The force of gravity acting on a planet is equal to its mass times its centripetal acceleration.
Fg = m v^2 / r
The force of gravity is defined by Newton's law of universal gravitation as:
Fg = mMG / r^2
Therefore:
mMG / r^2 = m v^2 / r
MG / r = v^2
v increases as r decreases. So the planet is moving fastest when it's closest to the sun, also known as the <em>perihelion</em>.
The change in velocity from 30 m/s north to 40 m/s south is a change of 70 m/s south
Water Could be Found in the frozen Ice on the moon. it would most likely be underground however