An object of mass 3kg is suspended by two light, inextensible strings. The strings make angles of 30degrees and 40degrees to the horizontal.
Find the magnitude of the tension in each spring.
T ' = tension in the string making an angle of 40° to the horizontal
By Lami's theorem,
T/sin(90° + 40°) = T '/sin(90° + 30°) = 3 * 9.81/sin(180° - 40° - 30°)
=> T = (3 * 9.81) * cos40°/sin70° N = 24 N
and T ' = (3 * 9.81) * cos30°/sin70° N = 27.1 N.
For Lami's theorem, please refer to the following link:
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