Understanding Forces in Tug of War: Positive, Negative, Zero

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In a tug of war, the winning team exerts a larger tangential force on the ground, leading to various work outcomes. The work done by the winning team on the losing team is zero, as the forces exerted on the rope and ground balance out. Similarly, the work done by the losing team on the winning team is also zero for the same reason. The work done by the ground on the winning team is positive due to friction aiding their motion, while the work done by the ground on the losing team is negative, as friction opposes their movement. Overall, the total external work done on the two teams is positive, reflecting the net force in the direction of motion.
harvik780
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I solved the following question but I am doubtfull about my results
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.
 
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a) the question asks for the work done by the winners on the losers. They apply just one force on the losers...through the rope. The force of the winners on the ground does not act on the losers.
b) also incorrect.
c)could be correct, unless the winners drag the losers toward them hand over hand on the rope while remaining still, instead of walking backwards.
d) Agree, except you meant to say the direction of the friction force on the losing team is opposite their direction of motion, didn't you?
e) Agree.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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