Question

What is the meaning of delta symbol? In the 2nd law of motion specially.

Answer 1

Newton's Second Law of motion states that the rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of the force.

ie., If initial momentum p1=mu

Final momentum p2=mv

Change in momentum ∆p=p2-p1

delta(∆) means change in any quantity.

Here 'delta p' means change in momentum.