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In tug of war,the team that exerts a larger tangential force on the ground wins.Consider the period in which a team is dragging the opposite team by applying larger tangential force on the ground.List which of the following works are positive,which are negative and which are zero?

a)Work done by the winning team on the losing team

b)Work done by the losing team on the winning team

c)Work done by the ground on the winning team

d)Work done by the ground on the losing team

e)total external work done on the two teams

answers and possible causes

a)Zero.As the the winning team applies two forces,one on the rope and the other on the ground.By newton's 3rd law the net force on the rope is zero at every point on the rope considering it's massless.So the work done by the winning team on losing team is zero

b)Zero.Same explanation as (a)

c)Positive.Considering the work done by the ground on the winning team is the work done by friction.We get that the direction of the this force on the winning team is in the direction of motion of the winning team.

d)Negative.Considering the work done by the ground on the losing team is the work done by friction.We get that the direction of the this force on the losing team is in the direction of motion of the losing team.

e)Positive.Considering that the net force on the system is in the direction of motion as frictional force on winning team is greater than the frictional force on losing team.

Also I want to know what role does the rope play,I mean how does the rope make the forces act on the two teams.