Answer:
a. Disk, 28 thousand light-years from
Explanation:
Since, a galactic disc is a component of disc galaxies, for instance spiral galaxies and lenticular galaxies. It consists of a stellar component and a gaseous component.
Also, the Sun lies within the galactic disk or in other words it is thought to be located in the galactic disk,
The Sun is located about 26,000 light-years away from the centre of the galaxy.
∵ From the given options 28,000 is nearest to 26,000
Hence, the sun is about 28 thousand light-years from the centre of the galaxy.
i.e. OPTION 'a' would be correct.
Answer:
(A) Angular speed 40 rad/sec
Rotation = 50 rad
(b) 37812.5 J
Explanation:
We have given moment of inertia of the wheel 
Initial angular velocity of the wheel 
Angular acceleration 
(a) We know that 
We have given t = 2 sec
So 
Now 
(b) After 3 sec 
We know that kinetic energy is given by 
Answer:
The approximate number of decays this represent is
Explanation:
From the question we are told that
The amount of Radiation received by an average american is 
The source of the radiation is 
Generally

Therefore 
Also 
Therefore 
An Average american weighs 88.7 kg
The total energy received is mathematically evaluated as

Cross-multiplying and making x the subject


Therefore the total energy deposited is 
The approximate number of decays this represent is mathematically evaluated as
N = 
Where n is the approximate number of decay
Substituting values
That's efficiency. There's no law that it must be stated in percent.
Answer:
ε = 2 V/cm
Explanation:
To calculate the mobility inside this bar, we just need to apply the expression that let us determine the mobility. This expression is the following:
ε = ΔV / L
Where:
ε: Hole mobility inside the bar
ΔV: voltage applied in the bar
L: Length of the bar
We already have the voltage and the length so replacing in the above expression we have:
ε = 2 V / 1 cm
<h2>
ε = 2 V/cm</h2><h2>
</h2>
The data of the speed can be used for further calculations, but in this part its not necessary.
Hope this helps