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प्रश्न
Two particles P and Q of mass 1 kg and 3 kg respectively start moving towards each other from rest under mutual attraction. What is the velocity of their center of mass?
उत्तर
Given,
Mass of particle P = 1 kg Mass of particle Q = 3 kg
Solution:
Particles P and Q form a system. Here no external force is acting on the system,
We know that M = `d/dt` (VCM ) = f
It means that C.M. of an isolated system remains at rest when no external force is acting and internal forces do not change its center of mass.
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संबंधित प्रश्न
The centre of mass is defined as \[\vec{R} = \frac{1}{M} \sum_i m_i \vec{r_i}\]. Suppose we define "centre of charge" as \[\vec{R}_c = \frac{1}{Q} \sum_i q_i \vec{r_i}\] where qi represents the ith charge placed at \[\vec{r}_i\] and Q is the total charge of the system.
(a) Can the centre of charge of a two-charge system be outside the line segment joining the charges?
(b) If all the charges of a system are in X-Y plane, is it necessary that the centre of charge be in X-Y plane?
(c) If all the charges of a system lie in a cube, is it necessary that the centre of charge be in the cube?
Consider the following the equations
(A) \[\vec{R} = \frac{1}{M} \sum_i m_i \vec{r_i}\] and
(B) \[\vec{a}_{CM} = \frac{\vec{F}}{M}\]
In a noninertial frame
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