Frictional force and Applied force has same “magnitude” and “opposite” direction.
Option: B
<u>Explanation</u>:
When a book is moved horizontally by applying “force” on the book, the frictional force is opposed to the book by the table. Here, this “frictional force” is opposing the book has the same force what we applied on the book but this frictional force and the applied force are opposite in direction. Always the “frictional force” is opposite to the “applied force” which stops the object to move. For example, if a force applied leftward to the object the frictional force is acted on the right side of the object.
When two objects are in contact they experience a "frictional force". This "frictional force" acts opposite to the force applied on to move the object.
Formula for "frictional force" is 
Where,
is coefficient of friction and N is normal force.
An element refers to a collection of atoms having the same number of protons and electrons (an atomic number). In each element there is a different atomic number due to a different amount of protons in the nucleus.
An isotope is a variation of an element that contains a different number of neutrons, therefore adding weight to the atom.
An ion is a charged atom, and its charge shows how many electrons it needs to gain or lose in order to become stable.
A. 14.59 is correctly rounded to 4 significant digits.
The word quark <span>originally appeared in a single line of the the novel Finnegans Wake written by the Irish author </span>James Joyce<span> (1882–1941). The protagonist of the book is a publican named Humphrey Chimpden Earwicker who dreams that he is serving beer to a drunken seagull</span>
B
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