Answer:
mass of the ball will be 1 kg
Explanation:
We have given force F = 0.5 N
This force must be equal to the centripetal force for the ball to revolve in the circle
So 
Centripetal acceleration is given as 
We have to calculate the mass of the ball
We know that force is given by

So 
m = 1 kg
So mass of the ball will be 1 kg
False
Explanation:
Called an asteroid for many years, Ceres is so much bigger and so different from its rocky neighbors that scientists classified it as a dwarf planet in 2006. Even though Ceres comprises 25 percent of the asteroid belt's total mass, tiny Pluto is still 14 times more massive.
Answer:
C. An external downward field is created or an external downward field is removed
Explanation:
As we can see that from the attached figure that the induced current would be counter clockwise. So the field occur because of induced current i.e. out of page. This represent that the current is induced in order to rise the flux out of the direction of the page
Therefore because of the external field, the field out of page & flux would be reducing or the external upward field is eliminated
So option C is correct
This room is called Substation