⇒⇒⇒⇒⇒L=21aStS2=21aRtR2(tRts)2=aSaR(21)2=gsinθgsinθ−μkgcosθ41=sin45∘sin45∘−μkcos45∘41=(21)(21)(11−μk)41=1−μk⇒μk=1−41=43=0.75
NEET UG 2025 — Physics Mechanics
There are two inclined surface of equal length (L) and same angle of inclination 45∘ with the horizontal. One of them is rough and the other is perfectly smooth. A given body takes 2 times as much time to slide down on rough surface than on the smooth surface. The coefficient of kinetic friction (μk) between the object and the rough surface is close to :
Held on 30 Apr 2025 · Verified 9 Jul 2026.
0.25
0.40
0.5
0.75
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