Answer:

Explanation:
= Avogadro's number = 
e = Charge of electron = 
k = Coulomb constant = 
Z = Atomic number of water = 18
M = Molar mass of water = 0.018 kg/mol
m = Mass of person
The charge is given by

Total number of protons and electrons in each sphere




Electrical force is given by

The electrostatic force of attraction between them is 
We use the following expression
T = 2*pi *sqrt(l/g)
Where T is the period of the pendulum
l is the length of the pendulum
and g the acceleration of gravity
We solve for l
l = [T/2*pi]² *g = [30s/2*pi]²* 9.8 [m/s²] = 223.413 m
The tower would need to be at least 223.413 m high
Because the number of valence electrons of an element determines the properties and in particular the reactivity of that element.
In fact, elements of the first group (i.e. only one valence electron) have high reactivity, because they can easily give away their valence electron to atoms of other elements forming bonds. On the contrary, elements of the 8th group (noble gases) have their outermost shell completely filled with electrons, so they do not have valence electrons, and they have little or no reactivity at all.
They all have segmented limbs, a hard exoskeleton, a pair of antennae and a segmented body.
<u>Answer</u>
3.7 Km south
<u>Explanation</u>
The definition of displacement is the distance traveled in a specific direction. It is the vector quantity. We add displacements like the way we add vectors.
Taking the direction towards North to be positive (+1.7 Km), the distance towards south would be negative (-5.4 Km).
Now lets add the two values.
(+1.7) + (-5.4) = 1.7 - 5.4
= - 3.7 Km But negative was towards south.
∴ Answer = 3.7 Km south.