Question

A 18-g paper clip is attached to the rim of a phonograph record with a diameter of 48 cm, spinning at 3.2 rad/s. What is the magnitude of its angular momentum (in kg m2/s)? Round your answer to the nearest ten-thousandth.

Answer 1

Answer:

Magnitude of its angular momentum = 0.0017 kgm²/s

Explanation:

Angular momentum, L = Iω

I is mass moment of inertia and ω is angular velocity.

Phonograph is in disc shape,

$\texttt{I for disc =}\frac{MR^2}{2}$

Radius = 0.5 x 48 = 24 cm = 0.24 m

Angular velocity, ω = 3.2 rad/s

Mass, M = 18 g = 0.018 kg

Substituting

     $L=\frac{0.018\times 0.24^2}{2}\times 3.2 =0.0017kgm^2/s$

Magnitude of its angular momentum = 0.0017 kgm²/s