Question

We use a sieve to separate sand and wheat grains, what should be the size of the holes of the sieve in comparison to the size of sand particles and wheat grains ?​

Answer 1

Answer:

If the size of particle it too small to be picked by hand,sieving is used for separating substances. A sieve; having pores of certain size is used. The bigger particles are retained by the sieve whereas the smaller particle are passed through it. For example; this method is used for separating bran from flour, sand from gravel, pearls of different sizes,etc.