In physics, a force is any interaction that, when unopposed, will change the motion of an object. A force can cause an object with mass to change its velocity to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity.
The simplest level at which life may exist is a cell
Answer: Though a hydrogen atom has only one electron, it contains a large number of shells, so when this single electron jumps from one shell to another, a photon is emitted, and the energy difference of the shells causes different wavelengths to be released... hence, mono-electronic hydrogen has many spectral lines.
Explanation: sry its late
