The document describes two monkeys, Chimpoo and McZee, climbing a rope together. Chimpoo can tolerate a maximum tension of 30 N on his tail. McZee weighs 2 kg. To carry McZee with him as they climb, Chimpoo must apply a force on the rope between 70 N and 105 N, as determined using Newton's Third Law and analyzing the forces as an interacting system accelerating upwards.

1. Chimpoo and McZee I see what you two naughty monkeys are doing … So , climbing is fun for you right… copyrights © youmarks.com

8. Applying Newton’s Third Law now copyrights © youmarks.com

11. Let us explain more telling you a story  Shall we…… So Chimpoo and McZee. What are they talking with each other? And can ropes talk? Lets find it out…… copyrights © youmarks.com

12. copyrights © youmarks.com McZee hold on, let me ask the rope if rope can pull us both upwards. Chimpoo pull me upwards…. . Rope Chimpoo, I can pull you upwards and for that you would not have to apply much force as I need to support your weight but to give you the support , I need some input from you which is your Action ( Mr. Newton told me to do so…)

13. You don’t understand rope. If I just give you an action equal to my weight which is 50N, you would not be pulling me with a force which is required to pull both of us together. What is the minimum force you need to pull both of us together? Rope Well , I have to atleast support your weight right? Which is atleast total of your weights which is 50 + 20 = 70 N copyrights © youmarks.com

14. Let me see how much McZee pulls me down because if he pulls me down with a force more than 30 N , I will die anyways. Don’t worry Chimpoo , my weight is 20N only and I am currently putting an action of 20 N only. So, your tail is not going to break out. . Thank God , So rope I can atleast hold McZee for another 10 N. Suppose McZee applies more force that is 30 N , how much I have to pull you down. Chimpoo that is a question which I will answer I think it would then allow me to move ahead as 20 N would go in supporting my weight and remaining 10 N would allow me to accelerate which is 10/ 2 = 5 m/s2. . copyrights © youmarks.com

15. But you accelerate at 5 m/s2, I would also have to accelerate at the same rate right because if I don’t you would just move over me… SO tell me rope how much force I have to apply on you if we both accelerate at 5 m/s2. Rope Pretty easy Chimpoo, I would need 70N to atleast pull you guys together and if you want to accelerat at 5 m/s2, I would need to support you guys for this acceleration too . So an additional force 5 * ( 5+2) = 35 N is needed to support you. So a total of 70 + 35 = 105 N, Can you give me that Chimpoo copyrights © youmarks.com

16. Ok . Rope we now have an option to give you a minimum of 70 N and we can go a maximum till 105 N , we would make sure while climbing , I pull you with a force in that range . Rope Thanks Chimpoo.. Happy Climbing ahead. copyrights © youmarks.com