Answer: Isaac Newton
Explanation: Isaac Newton is popularly remembered as the man who saw an apple fall from a tree, and was inspired to invent the theory of gravity. If you have grappled with elementary physics then you know that he invented calculus and the three laws of motion upon which all of mechanics is based.
C.) Electron shells or cloud! :)
Answer :D
Some characteristics shared by all electromagnetic waves are that they all travel at the same speed of light and their own transmission does not need medium. These wave types can also travel through empty spaces
Solution :
The angular acceleration, 
is obtained from the equation of the 
of rotational motion,
Thus,
or 
where 
is torque, F is force, d is moment arm distance, I is the moment of inertia
Thus, 
Now if the force and the moment arm distance are constant, then the 
That is when, F = d = constant, then 
.
Thus, moment of inertia, I is proportional to mass of the bar.
The mass is less for the bar in case (1) in comparison with that with the bar in case (2) due to the holes that is made in the bar.
Therefore, the bar in case (1), has less moment of inertia and a greater angular acceleration.
The magnitude of the kinetic friction force, ƒk, on an object is. Where μk is called the kinetic friction coefficient and |FN| is the magnitude of the normal force of the surface on the sliding object. The kinetic friction coefficient is entirely determined by the materials of the sliding surfaces. hope it helps
