question_answer

  Deduce Newton's first law from the second law.

Answer:

                  According to second law, F = ma                 If F=0, a = 0 since  ,                        But or, v-u = 0 so, v = u for whatever time t is taken. This means that the object will continue moving with uniform velocity, u throughout the time, t. If u is zero then v will also be zero. That is, the object will remain at rest.