Density applies to many if not all aspects of life. With density you can explain why ice floats. You can explain why oxygen is on the earth, and not floating around in space( or being replaced by another gas). You can also explain why heat rises while cold air sinks.
If one of two interacting charges is doubled, the force between the charges will double.
Explanation:
The force between two charges is given by Coulomb's law
K=constant= 9 x 10⁹ N m²/C²
q1= charge on first particle
q2= charge on second particle
r= distance between the two charges
Now if the first charge is doubled,
we get 
F'= 2 F
Thus the force gets doubled.
Answer:
La expansión no es más que el incremento con el tiempo de la distancia entre cualquier par de galaxias lejanas. Se suele utilizar para representar este hecho la analogía de un globo donde hemos pintado una serie de puntos a modo de galaxias.
Explanation:
Answer with Explanation:
The force of attraction between 2 charges of magnitude
separated by a distance 'r' is given by
where
is a constant known as permitivity of free space
Applying the given values in the above relation we get
C a meter stick with only centimeters
D a ruler with millimeters and centimeters
D would be to the nearest half milimeter. Take some time to measure with a 2 inch ruler. Would you really need to know the length to half a mil ?
