A body of mass 1 kg is suspended by two strings as shown in the original figure. The left and right strings make angles 60° and 30° with the horizontal respectively. If g = 10 m/s², the magnitudes of tensions T₁ and T₂ respectively are:

Question

G1 Physics · Accepted Answer

The body is in equilibrium under three concurrent forces T₁, T₂ and weight mg = 10 N. From the geometry in the original figure, the angles between the three forces are: angle between T₁ and T₂ = 90°, angle between T₂ and weight = 120°, angle between weight and T₁ = 150°. By Lami's theorem, T₁/sin120° = T₂/sin150° = 10/sin90°. Therefore, T₁ = 10 sin120° = 10(√3/2) = 5√3 N, T₂ = 10 sin150° = 10(1/2) = 5 N. Correct option: A.