Answer:
Explanation:
From the question we are told that
The moment of inertia is 
The final angular speed is 
The time taken is 
The initial angular speed is 
Generally the average angular acceleration is mathematically represented as

=> 
=> 
Generally the torque is mathematically represented as

=> 
=> 
Explanation:
(a)
Critical angle is the angle at the angle of refraction is 90°. After the critical angle, no refraction takes place.
Using Snell's law as:
Where,
is the angle of incidence
is the angle of refraction = 90°
is the refractive index of the refraction medium
is the refractive index of the incidence medium
Thus,
The formula for the calculation of critical angle is:
Where,
is the critical angle
(b)
No it cannot occur. It only occur when the light ray bends away from the normal which means that when it travels from denser to rarer medium.
The light bulb converts electrical energy into light and heat.
Good luck! (:
We will use the ideal gas equation:
PV = nRT, where n is moles and equal to mass / Mr
P = mRT/MrV
P = 15.4 x 8.314 x (22.55 + 273) / 32 x 4.44
P = 266.3 kPa