A weight of 4.33 N is suspended by the string fasten at its upper end. A horizontal force is applied to the weight so that the string makes an angle of 30 degrees with the vertical. Find the horizontal force and the tension in the spring.

Answer 1

Balance vertical forces on the weight.

Vertical:
T cos 30 - M g = 0

Solve for tension, T

Then balance the horizontal forces, including the applied force, F.

F - T sin 30 = 0

F = T/2 = (1/2)M*g/cos30 = M*g/sqrt3