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Motion — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceMotion3 Marks
Question
Define acceleration and state its $SI$ unit. For motion along a straight line, when do we consider the acceleration to be:
  1. Positive.
  2. Negative? Give an example of a body in uniform acceleration.
✓

Answer

  1. Acceleration is the rate of the measure of the change in the velocity of the moving object per unit time. Si unit is $ms^{-2} = m/s^2$
  1. If the object moving along the line is positive. same direction.
  2. If the object is moving in the opposite way it is negative. opposite direction.
  1. The motion of a freely moving body is the example of uniform acceleration.

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