AB is a uniform bar of length 5m and weighs 60N. It is supported in a horizontal position by two vertical strings P and Q. P is 0.5m from A and Q is 1.5m from B. (a) What are the tensions in the strings? (Ans= 20N and 40N) (b) What weight must be applied to A if the tensions in the strings are to be equal? (Ans= 15N) (c) What is the biggest mass which can be hung from B if the bar is to remain horizontal? (Ans= 4.1kg) My teacher gave us the answers to these questions. I have gotten part (a), but I truly am lost with (b) and (c). For some reason I keep getting (b) to be 0N... I would really appreciate any help and explanations. Thanks.