Question

- + Fit to page Page Let's see how valuable free body diagrams are to solve a problem we know from the real world containing friction. There are 2 versions to this homework. You can A) do the challenge version with the rope pulled at an angle, or B) the version with a horizontal rope. Version A needs a bit of trigonometry but also keeps us honest and reminds us that the normal force is not always equal in magnitude to the weight mg. Have fun 1. Have you used a good old Davos wood toboggan just like the one I brought from Germany 10 years ago? Could you believe that I could not find one here in the stores? Assume you (you know your mass M) are pulling a child on a sled (mass of the child is m= 23kg) along a snow covered horizontal road using a 1.1m long rope. The friction coefficient between the metal runners of the sled and the ground is UK. = 0.020. Picture A) 8 1.1m 0=25 Ps=? Hx=0.02 Picture B) Hx=0.02 a) What friction coefficient do you need on your shoes to make sure you are not starting to slip while pulling the child? b) Now how does that change when the child is stubbom and puts his feet in the snow to slow you down, and his heels having a friction coefficient in the snow of 0.90. c) Can you accelerate the child and drag him along, when the friction coefficient of your shoes is 0.30 (which is about a normal shoe). d) What is the highest acceleration you can reach before you start slipping?

Have you used a good old davos wood toboggan just like the one I brought from Germany 10 years ago?
picture B please with explanation for each if possible.

Answer 1

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nled th child can accelerate thu man Hunca thon mau But ithe child buto his teat in launot acelunatt him ( Aruwer d) thuchild i on led, thun marimum alingm mim ,T = Nwton's econd Law T ma э иМg - .30 xSox9 81 m a o-o 2 x2398 X 23 Xa 147.15 4-S126 = 23 a 6 2 m a "/-(Arnurd 2