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## Homework Statement

A muscle builder holds the end of a massless rope. At the end of the rope, a 15 kg ball is hung as shown in the figure. What is the tension in the rope if the angle [tex]\theta[/tex] in the drawing is 4.5[tex]^{}o[/tex]?

## Homework Equations

g = 9.8m/s[tex]^{}2[/tex]

F = mg

Trigonometrical functions

## The Attempt at a Solution

I attached a picture. My answer is just totally wrong... but I have no idea what I'm doing wrong. Please could you help out. I apologise for any stupid mistakes!

The ball is being pulled by the two hands, forming a triangle that can be divided into two right triangles with sides labeled a1, b1, c1 and a2, b2, c2 respectively.

θ Is given as 4.5°

b1 = b2 = mg = 9.8N x 15N (weight of ball given as 15kg = 15N, gravitational pull is 9.8m/s2 = 9.8N)

= 147N

The tension of the rope would equal the force created by the hands pulling (a1 and a2) and a1 = a2.

sinθ = a1/b1

∴ a1 = b1 sinθ

= (147N)sin4.5°

= 12N