A box weighing 180 newtons is hanging by rope as shown in the figure. Find the tension T2.
A. 81 newtons
B.
171 newtons
C. 130 newtons
OD. 85 newtons

A box weighing 180 newtons is hanging by rope as shown in the figure Find the tension T2 A 81 newtons B 171 newtons C 130 newtons OD 85 newtons class=

Respuesta :

Answer:

B. 171 N

Explanation:

The equation of the forces along the horizontal and vertical directions are:

Horizontal:

[tex]T_2 cos 62^{\circ} = T_1 cos 20^{\circ}[/tex] (1)

Vertical:

[tex]T_1 sin 20^{\circ} + T_2 sin 62^{\circ} = W[/tex] (2)

Where W = 180 N is the weight of the box.

From (1),

[tex]T_2 \frac{cos 62^{\circ}}{cos 20^{\circ}} = T_1 [/tex]

Substituting into (2),

[tex](T_2 \frac{cos 62^{\circ}}{cos 20^{\circ}}) sin 20^{\circ} + T_2 sin 62^{\circ} = W\\T_2 (cos 62^{\circ} tan 20^{\circ}+sin 62^{\circ})=W\\T=\frac{W}{cos 62^{\circ} tan 20^{\circ}+sin 62^{\circ}}=171 N[/tex]