Answer:

Explanation:
The index of refraction is equal to the speed of light c in vacuum divided by its speed v in a substance, or
. For our case we want to use
, which for our values is equal to:

Which we will express with 3 significant figures (since a product or quotient must contain the same number of significant figures as the measurement with the <em>least</em> number of significant figures):

Answer:
12 kgm²
Explanation:
here angular acceleration = 10rad/sec²
torque= 120Nm
moment of inertia=?
we know,
torque= angular acceleration× moment of Inertia
or, moment of inertia = torque/angular acceleration
= 120/10
= 12kgm²
Acceleration....................................... <span />