Answer:
The magnitude of the angular acceleration is 
Explanation:
From the question we are told that
The angular speed of CD is 
time taken to decelerate is 
The final angular speed is 
The angular acceleration is mathematically represented as

substituting values


The negative sign show that the CD is decelerating but the magnitude is

Answer:
(a) 
(b) 
Explanation:
(a) The surface current density of a conductor is the current flowing per unit length of the conductor.

Considering a wire, the current is uniformly distributed over the circumferenece of the wire.

The radius of the wire = a

The surface current density 
(b) The current density is inversely proportional
......(1)
k is the constant of proportionality

........(2)
substituting (1) into (2)





substitute 

Answer:
C. Neutral
Explanation:
Ions will combine in a way that the overall ionic compound will always be neutral.
Answer:
<h2>
96 Joules</h2>
Explanation:
We know that efficiency is the ratio of output power by input power. i.e. Efficiency describes the quality of machine or system how good it is.
Solution,
Energy input of system = 120 J
Efficiency = 80% = 
Now,
According to definition,
Efficiency = 
Cross multiplication:

Calculate the product

Hope this helps...
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