- #1

Arman777

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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 ?

**Rotational Kinematics Equations**

2. Homework Equations

2. Homework 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 dont 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