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Homework Statement
[/B] A flywheel with a D=1.2m is rotating at an angular speed of 200 rev/min
(a) Whats the angular speed in rad/s ?
(b)Whats v=? in the point on the rim ?
(c)What const. ∝ ( in rev/min^2) will increase its angular speed to 1000 rev/min in 60 sec ?
(d)How many revolutions does the wheel make during that 60 sec ?
2. Homework Equations
Rotational Kinematics Equations
The Attempt at a Solution
[/B] I found a,b,c correctly (for long tries ) but I stucked at d.
I guess I ll use here ##Δθ=wt-1/2∝t^2##
(a) w=20.9 rad/s
(b)v=12.5
(c)=800 rev/min^2
Now for d,
lets to write all equaiton in rev/min form so
20.9rad/sec=20.9.2π.60=7879 rev/min
I don't know what will be the left part cause Δθ in units its normally just rev I guess so
θ-200rev/min=7879rev/min.1min+1/2 (800rev/min^2).(1 min)^2
Here I get a huge number...
Thank you