Understanding the Price Elasticity of Supply

It is understandable from the law of supply that- if price goes up, the supply will also increase. But the law of supply cannot determine how much the supply will rise with respect to the increase in the price. For this we need the concept of the elasticity of supply in order to measure the extent of the quantity supplied in response to the price change. In simpler words, price elasticity of supply is defined as the percentage change in quantity supplied by the percentage change in the price.
The price elasticity of supply can be formulated as:
Es = %change in quantity of supply/%change in the price of the article, where Es is the price elasticity of supply.
If Q be the quantity of supply of the article and P be price of the same, then price elasticity of supply (pes) may be expressed as:
Es = dQ/Q ÷ dP/P
     = (dQ/dP)×(P/Q)
where dQ and dP are the percentage change in the quantity of supply and the percentage change in price of the article respectively.