That can only be happening if the mass mysteriously increased somehow. I'd like to know how in the world THAT happened.
Answer:
Explanation:
Given
mass of balls 

angular velocity 
Length of Rod 
Tension in the Second half of rod



For First Part





Answer:
Water cannot be used in thermometer because of its higher freezing point and lower boiling point than other liquids . If water is used in a thermometer , it will start phase change at 0
C and 100
C and will not measure temperature , out of this range . This range is very small as compared to other liquids as mercury , having freezing point about −39
C and boiling point 356
C.
Explanation:
For this problem, we use the Coulomb's law written in equation as:
F = kQ₁Q₂/d²
where
F is the electrical force
k is a constant equal to 9×10⁹
Q₁ and Q₂ are the charge of the two objects
d is the distance between the two objects
Substituting the values:
F = (9×10⁹)(-22×10⁻⁹ C)(-22×10⁻⁹ C)/(0.10 m)²
F = 0.0004356 N