The state of matter depends upon how close the individual particles are together
-- The product of the magnitudes of the two charges.
-- The distance between the centers of the two charges.
The signs of the charges ... whether their signs are the same
or opposite ... determines the direction of the forces, but not
their magnitude.
Pour the entire components into water.
First the iron filings can be separated using a magnet as iron is a magnetic element.
By pouring the mixture into water, it allows the salt to dissolve in the water, while the sand will not.
Next we can run this solution through a filtration device to separate the sand from the water.
Now all that's left is to let the water evaporate so that the salt will be exposed that dissolved into the water.
Get your numbers gathered up and solve the problem in the ordered step
heat from water goes into air in ball
air expands
ping goes the dent