As science being dynamic many things will change and due to this changes many things and theories will be new to us. the model of the atom is not weak, it is just developing as time progress because in the early times it is not fully understood because of the lack of technology to study, what scientist do is just filling the knowledge gap of the previous studies.
Force applied by the lever to the object=2700 N
Explanation:
Mechanical advantage= 
mechanical advantage= 5.4
effort force= 500 N
we need the load force
5.4= load/500
load=2700 N
Thus the force applied by the lever to the object=2700 N
Answer:As a noun relative means a person who is connected with others by blood.