CBSE-XI-Physics
09: Centre of Mass, Linear Momentum, Collision
- #12If the linear momentum of a particle is known, can you find its kinetic energy? If the kinetic energy of a particle is know can you find its linear momentum?Ans : Yes, the kinetic energy of the particle can be determined if the value of linear momentum is known.
The kinetic energy is calculated using the formula:
`` \,\mathrm{\,K \,}.\,\mathrm{\,E \,}=\frac{1}{2}m{v}^{2}=\frac{{p}^{2}}{2m}``
`` w\,\mathrm{\,here \,},p\mathit{}\,\mathrm{\,is \,}\,\mathrm{\,the \,}\,\mathrm{\,linear \,}\,\mathrm{\,momemtum \,}\,\mathrm{\,having \,}\,\mathrm{\,value \,}mv.``
But linear momentum cannot be determined even if the kinetic energy is known because linear momentum is a vector quantity, whereas kinetic energy is a scalar quantity. Thus, the direction of the linear momentum remains unknown, however its magnitude can be calculated.
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