The strip placed n a pivot and kept in equilibrium by forces as shown in figure below

The strip placed n a pivot and kept in equilibrium by forces as shown in figure below


(i) Determine the value of F and R
(ii) X is the distance from the end of the plank to the point of application of force F. Force F is now applied at various points nearer to the pivot so that x increases. Equilibrium is maintained all the time. On the axes provided sketch the relation between force F and x.


(iii) Give a reason for the answer in (ii) above

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(i)
Taking moment about R
20F = 15 x 4.86
F= 15 x 4.86 = 3.645N
R= F + W
= 3.645 + 4.86 = 8.51 N
Taking moment about F
20R = 4.86 x 35 = 8.505N
thus, F = R – W
= 8.505 – 4.86
= 3.645N

(ii)


(iii) As X increases the distance between F and pivot reduces so F has to increase to maintain equilibrium.

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Wilfykil answered the question on March 27, 2019 at 12:54

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