When brakes of a car are applied, angular velocity of a flywheel reduces from 900 cycles/min to 720 cycle/min in 6sec. Angular retardation is _.
Correct answer: A. π rad/s2
- A. π rad/s2
- B. 9π rad/s2
- C. 8π rad/s2
- D. None of these
Explanation
Correct Option: A The initial angular velocity (ωi) is given as 900 cycles/min. To convert it to radians per second, we can multiply by 2π/60 since there are 2π radians in one revolution and 60 seconds in one minute:ωi = (900 cycles/min) * (2π/60) rad/s = 30π rad/sThe final angular velocity (ωf) is given as 720 cycles/min. Converting it to radians per second:ωf = (720 cycles/min) * (2π/60) rad/s = 24π rad/sThe change in angular velocity (Δω) is then:Δω = ωf - ωi = 24π rad/s - 30π rad/s = -6π rad/sThe negative sign indicates that the angular velocity is reducing.The time taken (t) is given as 6 seconds.The angular retardation (α) can be calculated using the formula:α = Δω / tSubstituting the values:α = (-6π rad/s) / 6 s = -π rad/s²Therefore, the angular retardation is -π rad/s². However, if we consider the magnitude of the angular retardation, it is equal to π rad/s².=
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