2nd Law: F=ma
a= change in velocity/time
a=F/m
say both objects must accelerate at a=2 m/s^2
object A is a wood plank, which is roughly 10 kg
object B is my metal ball, which has a mass of 100kg
now, solving for F applied to both objects
Fwood=(10kg)(2 m/s2)= 20 N
Fmetal=(100kg)(2 m/s2)= 200 N
the F needed to move the metal ball is 10 times greater than the F needed to move the wood plank. Hope this helped, I'm about to go fail my physics exam :)