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The Centre of Mass of a System of Particles is at the Origin. It Follows that - Physics

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प्रश्न

The centre of mass of a system of particles is at the origin. It follows that

विकल्प

  •  the number of particles to the right of the origin is equal to the number of particles to the left

  •  the total mass of the particles to the right of the origin is same as the total mass to the left of the origin

  • the number of particles on X-axis should be equal to the number of particles on Y-axis

  •  if there is a particle on the positive X-axis, there must be at least one particle on the negative X-axis

  • none of these

MCQ

उत्तर

None .

The centre of mass of a system of particles depends on the product of individual masses and their distances from the origin.
Therefore, we may say about the given statements:
(a) Distance of particles from origin is not known.
(b) Masses are same but the distance of particles from the origin is not given.
(c) Distance of particles from origin is not given.
(d) It is not necessary that least one particle lies on the negative X-axis. The particles can be above the negative X-axis on X-Y plane. 

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अध्याय 9: Centre of Mass, Linear Momentum, Collision - MCQ [पृष्ठ १५८]

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एचसी वर्मा Concepts of Physics Vol. 1 [English] Class 11 and 12
अध्याय 9 Centre of Mass, Linear Momentum, Collision
MCQ | Q 1 | पृष्ठ १५८

संबंधित प्रश्न

If all the particles of a system lie in X-Y plane, is it necessary that the centre of mass be in X-Y plane?


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Consider the following the equations
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  1. Show pi = p’+ miV Where pi is the momentum of the ith particle (of mass mi)  and p′ i = mi v′ i. Note v′ i is the velocity of the ith particle relative to the centre of mass. Also, prove using the definition of the centre of mass `sum"p""'"_"t" = 0`
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