How to do 189th question?

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1 Answer
Mar 30, 2018

(2)

Explanation:

A force

P = (0,0,-m g)

shall be decomposed as the sum

P = F_1+F_2+F_3 with

F_1 = f(cos30^@,sin30^@,sin30^@)
F_2 = f(-cos30^@,sin30^@,sin30^@)
F_3 = f(0,-1,sin30^@)

then with the third component

-mg = 3fsin 30^@ hence

absf = (mg)/(3sin30^@) = 2/3mg