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Navneet Sharma posted an Question
September 02, 2020 • 16:39 pm 30 points
  • IIT JAM
  • Physics (PH)

Please explain how the r.h.s of equation in box comes?

Physics (Mechanics) Example : A body of mass 'm' falls from rest at a height h under gravity (acceleration due to g) through a dense medium which produces resistive force F = -kv, where k is a conserve and 'v is the speed. It will hit the ground with a kinetic energy ? Solution: F = ma, TIPS Drag Force Always Applied opposite to the velocity. mg kv2 = maa (6) in Terms of Position (x) X = 0Qu = 0 dv mg- kV2 = mv- dx h F=-kv dv kv2 dx9 +X m mg vdv = dx x = h g-V m Integrating both sides vdv - - fdx og-2 m k g 2=t m Let 2y dv dt m m vdv -dt 2k m dt = X 2k t 2kx log, (t) = m g- m log om 2kx m g 2kx kv2 e m

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    Ruby negi best-answer

    did u want only this part clarification? for any further doubt, do let me know.. here ball is coming down so mg is more than the resistive force that oppose it to come down .. applied Newton's second law equation..... after this boxed equation, hope everything is clear.

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