1 One end of a light inextensible string is attached to a block. The string makes an angle of \(\theta ^ { \circ }\) with the horizontal. The tension in the string is 20 N . The string pulls the block along a horizontal surface at a constant speed of \(1.5 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) for 12 s . The work done by the tension in the string is 50 J . Find \(\theta\). [3]