MHT CET202019 Oct 2020Evening ShiftPhysicsLaws of MotionActual
A child starts running from rest along a circular track of radius ' r ^ ' with constant tangential acceleration 'a'. After time 't' he feels that slipping of shoes on the ground has started. The coefficient of friction between shoes and the ground is [ g = acceleration due to gravity ]
Options
- A[a² t²+a⁴ r⁴ ] r g
- B[a⁴ t⁴+a² r² ] r g
- C[a⁴ t⁴+a² r² ]^ 1 2 g r
- D[a⁴ t⁴-a² r² ]^ 1 2 r g
Correct answer
C. [a⁴ t⁴+a² r² ]^ 1 2 g r
Step-by-step solution
(D) After time t, velocity V = at radial acceleration a_ r = V² r = a² t² r Total acceleration = a⁴ t⁴ r² +a² g= a⁴ t⁴+a² r² r² = [a⁴ t⁴+a² r² ]^ 1 2 g r