question_answer

Give examples to show that a positive acceleration can be associated with a 'slowing down' and a negative acceleration with a 'speeding up'.

Answer:

                The slope of distance-time graph of a uniformly accelerated motion in one dimension represents the instantaneous velocity. The slope of distance-time graph of a uniform motion in one dimension represents the uniform velocity of the moving body. The slope of velocity-time graph of uniformly accelerated motion at a given instant represents the acceleration of the moving body at that given instant. For the distance time graph of an accelerated motion, the positive value of slope represents that the velocity of the moving body is increasing with time and the negative value of slope represents that the velocity of the moving body is decreasing with time. Similarly for the velocity-time graph of a uniformly accelerated motion, the positive value of slope represents that the acceleration is positive i.e. the body is accelerated and negative value of slope represents that the acceleration of body is negative i.e. the body is retarded.