posted by Tony on .
A particle of mass 4kg is suspended from a point A on a vertical wall by means of a light inextensible string of length 130cm.A horizontal force P, is applied to the particle so that it is held in equilibrium a distance of 50cm from the wall. Find the value of P and the tension in the string.
50/130 is the sine of the angle the string makes with the wall. That angle is therefore A = 22.6 degrees. (The string, wall and horizontal form a 5-12-13 right triangle)
Now write horizontal and vertical force balance equations and solve for P and T. (T is the tension)
The vertical equilibrium equation will be:
T cos22.6 = M g
so you can already solve for T.
The horizontal equilbrium equation is
T sin22.5 = P
You finish it.