A :-) for this question , we should apply 
F = ma 
( i ) Given - m = 2 kg 
 a = 15 m/s^2
Solution : 
F = ma 
F = 2 x 15 
F = 30 N 
( ii ) Given - m = 2 kg 
 a = 10 m/s^2
Solution : 
F = ma 
F = 2 x 10 
F = 20 N 
.:. The net force of object ( i ) has greater force compared to object ( ii ) by 
( 30 - 20 ) 10 N 
        
             
        
        
        
Answer:
The specific question is not stated, however the general idea is given in the attached picture. The electric field in each region can be found by Gauss’ Law. 
at r < R:
Since the solid sphere is conducting, the total charge Q is distributed over the surface, and the electric field inside the sphere is zero. 
E = 0. 
at R < r < 2R:
The electric field can be found by Gauss’ Law as in the attachment. The green pencil shows this exact region. 
at 2R < r:
The electric field can again be found by Gauss’ Law, the blue pencil shows the calculations for this region. 
Explanation:
Gauss’ Law is straightforward when applied to spheres. The area of the sphere is  , and the enclosed charge is given in the question as Q for the inner sphere, and 2Q for the whole system.
, and the enclosed charge is given in the question as Q for the inner sphere, and 2Q for the whole system. 
 
        
             
        
        
        
<span>every magnet you interact with on a daily basis has two poles: a north and a south pole. Fridge magnets are permanent ferromagnets, and their magnetic field is generated by the alignment of their internal magnetic domains. A magnet sticks to a fridge not because the "fridge's pole" is opposite in sign to the "magnet pole" - the magnet always has two poles - but rather because the magnetic domains in the iron/steel of the fridge door align with the magnet field created by the permanent magnet, creating a 'new magnet" on the region it touches on the fridge. Both the north and south pole of a magnet will stick to a fridge, as well the side of the magnet containing both north and south poles.</span>