Question

A
À sphere of mass 2kg and the
radius
5 cm is rotating at
the rate of
3oo rpm Calculate the torque required
to stop in
6.28 revolutions. Moment
of Inertia of the sphere about any
diameter 2/5 MR²
​

Answer 1

Answer:

=2kg,R=5cm=5×10

−2

m,

ω

0

=300rev/min=

60

300×2π

=10πrad/s

θ=2πrev=2π×2 pi=4π

2

rad

α=?ω=0

α=

2θ

ω

2

−ω

0

2

=−

2×4π

2

100π

2

=−

2

25

rad/s

2

τ=Iα

=

5

2

MR

2

α=

5

2

×2×(5×10

−2

)

2

×

2

25

=2.5×10

−2

Nm