JEE Main202331 Jan 2023Evening ShiftPhysicsLaws of MotionActual
A body of mass 10 kg is moving with an initial speed of 20 m s - 1 . The body stops after 5 s due to friction between body and the floor. The value of the coefficient of friction is: (Take acceleration due to gravity g = 10 m s - 2 )
Options
- A0 . 2
- B0 . 3
- C0 . 5
- D0 . 4
Correct answer
D. 0 . 4
Step-by-step solution
Friction force wil act opposite to the motion of the body. F = μ N = μ m g ⇒ a = - μ g -ve sign for direction relative to the motion of body Now, applying equation of motion, we get v = u + a t ⇒ 0 = 20 + - μ × 10 × 5 ⇒ 50 μ = 20 ⇒ μ = 0 . 4