Question

An electric motor rotating a workshop grinding wheel at 1.06 102 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 2.10 rad/s2. (a) How long does it take the grinding wheel to stop

Answer 1

t = 106π / 30*2.1

Step-by-step explanation:

`w_(i) = 1.06*10^(2)` => 106

=> 106 x 2π/60

=> 106/30π

∝ = -2.1 rad/sec²

`w_(f)` => 0

`w_(f)` =
`w_(i)` + ∝t

∴ (
`w_(f)` -
`w_(i)`) / ∝ = t

t = 106π / 30*2.1