Answer:
all the forces occur in pairs that if one object exerts a force on another object, then the second object exerts an equal and opposite reaction force on the first.
Answer:
Explanation:
Given
mass of person is m
Distance between bridge and river is h
chord has an un-stretched length of 
Let spring constant be k
Person will just stop before hitting the river
Conserve energy i.e. Potential Energy of Person is converted in to elastic energy of chord




Thus 
Answer:
tell ke first ,what will happen in zero gravity?
Answer:k=28.29 kN/m
Explanation:
Given
mass 
height from which Elevator falls 
Let x be the compression in the spring
thus From conservation of Energy Potential energy will convert in to Elastic Potential Energy of spring
----------1
also maximum acceleration is 5g
thus

here 


Substitute x in equation 1




