Friction force wil act opposite to the motion of the body.
F=μN=μmg
⇒a=−μg(-ve sign for direction relative to the motion of body)
Now, applying equation of motion, we get
v=u+at
⇒0=20+(−μ×10)×5
⇒50μ=20
⇒μ=0.4
JEE Main 2023 — Physics Mechanics
A body of mass 10kg is moving with an initial speed of 20ms−1. The body stops after 5s due to friction between body and the floor. The value of the coefficient of friction is: (Take acceleration due to gravity g=10ms−2)
Held on 31 Jan 2023 · Verified 6 Jul 2026.
0.2
0.3
0.5
0.4
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