How to Calculate the Weight of an Object Using Tension and Angles

What is the weight of an object held by two cables with a tension of 30 N each, making an angle of 45° with the horizontal?

A) 10.2 N

B) 21.2 N

C) 32.4 N

D) 42.4 N

Answer: option D) 42.4 N

Calculation of the Weight of the Object

The weight of the object is balanced by the vertical component of tension.

W = T sin θ + T sin θ = 2 T sin θ

The tension in each cable is T = 30 N

Angle made by the cables with the horizontal, θ = 45°

Therefore, W = 2 × 30 N × sin 45° = 2 × 30 N × 0.707 = 42.4 N