Home
Class 11
PHYSICS
A flywheel rotating at 420 rpm slows dow...

A flywheel rotating at `420` rpm slows down at a constant rate `2 rad s^(-2)`. What time is required to stop the flywheel ?

A

22 s

B

11 s

C

44 s

D

12 s

Text Solution

Verified by Experts

The correct Answer is:
A

(a) Here, `v_0 = 420 rpm = 7 rps`
:. `omega_0 = 2 pi v_0 = 2 xx (22)/(7) xx 7 = 44 rad s^-1`
`omega = 0, prop = -2 rad s^-2`
`t = (omega - omega_0)/(prop) = (-44)/(-2) = 22 s`.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ROTATIONAL DYNAMICS

    A2Z|Exercise Torque , Torque Equation And Equilibrium Of A Rigid Body|29 Videos
  • ROTATIONAL DYNAMICS

    A2Z|Exercise Angular Momentum And Its Conservation|30 Videos
  • ROTATIONAL DYNAMICS

    A2Z|Exercise Moment Of Inertia|39 Videos
  • PROPERTIES OF MATTER

    A2Z|Exercise Chapter Test|29 Videos
  • THERMAL PROPERTIES OF MATTER

    A2Z|Exercise Chapter Test|30 Videos

Similar Questions

Explore conceptually related problems

A flywheel rotating at 420 rpm slows sown at a constant rate 2 rad s^(-2) . What time is required to stop the flywheel ?

A flywheel rotating at the rate of 120 rpm slows down at a constant rate of 2 rad s^(-2) . What time is required to stop the flywheel and how many rations does it make in the process ?

Knowledge Check

  • A flywheel is revolving at 150 revolutions per minutes .If deccelerates at a constant rate of 2 pi rad //s^(2) , then time requred to stop it is

    A
    `10 s`
    B
    `5 s`
    C
    `2.5 s`
    D
    `1.25 s`
  • Similar Questions

    Explore conceptually related problems

    The motor of engine rotating at an angular velocity of 500 rpm slows down at a constant rate of 2.5rads^(-2) . Calculate the time required to stop the motor.

    Just as a helicopter is landing, its blades are turning at 30.0 rev/s and slowing at a constant rate. In the 2.00 min required for them to stop, how many revolutions do they make?

    A flywheel of mass 1 metric ton and radius 1 m is rotating at the rate of 420 rpm. Find the constant retarding torque required to stop the wheel in 14 rotations, assuming mass to be concentrated at the rim of the wheel.

    A sledge and its rider, with a total mass of 85 kg, emerge fro a downhill track onto a horizontal straight track with an initial speed of 37 m/s. If a force slows them to a stop at a constant rate of 2.0 m//s^(2) , (a) what magnitude F is required for the force, and (c) what work W is done on them by the force ? What work W is done on them by the force ? What are (d) F, (e) d, and (f) W if they, instead, slow at 4.0 m//s^(2) ?

    A flywheel of moment of inertia 10^(7) g cm^(2) is rotating at a speed of 120 rotations per minute. Find the constant breaking torque required to stop the wheel in 5 rotations.

    A flywheel with a diameter of 1.20 m is rotating at an angular speed of 200 rev/min. (a) What is the angular speed of the flywheel in radians per second? (b) What is the linear speed of a point on the rim of the flywheel? ( c) What constant angular acceleration (in revolutions per minute-squared) will increase the wheel's angular speed to 1000 rev/min in 60.0 s? (d) How many revolutions does the wheel make during that 60.0 s?

    A flywheel of mass 25 kg has a radius of 0.2 m. What force should be applied tangentially to the rim of the flywheel so that it acquires an angular acceleration of 2 "rad s"^(-2) ?