Answer:
usually x-ray tube filaments are devices that limit the current flow i.e. current cannot easily pass through them or we can say that they are current limited devices. So to allow fine electron transmission control by filament heating current, rhenium must not be used in x-ray tube filaments.
change in position of an object we use the
symbol ∆×\ delta×∆×for displacement, where ∆. means
"change" ∆ vector quantity with units of distances start
text ,d,I,s,t,a,n,c,e , end text.
Answer:
Noise level will be -18.2 watt
So option (b) will be correct answer
Explanation:
We have given sound intensity 
And threshold intensity 
( in question it is given as 
but its standard value is 
)
Now noise level 
So the noise level will be -18.2
So option (b) will be correct answer
