A particle P of weight W newtons is attached to one end of a light inextensible string - Edexcel - A-Level Maths Mechanics - Question 1 - 2014 - Paper 2

To find the tension in the string, we can analyze the forces acting on the particle P. The horizontal force (5 N) and the vertical component of the tension must maintain equilibrium.

Using the horizontal component:

$5 = T \cos(25^{\circ})$

From this, we can solve for T:

$T = \frac{5}{\cos(25^{\circ})}$

Evaluating this gives:

$T \approx \frac{5}{0.9063} \approx 5.52 \text{ N}$

Next, resolving vertically, since P is in equilibrium:

The vertical component of tension is:

$T \sin(25^{\circ}) = W$

Thus, we can refine the equation:

$W = T \sin(25^{\circ})$

As established, substituting our previous T calculation leads us to the solution.