WAEC - Physics (1989 - No. 3)
A boy pulls a nail from the wall with a string tied to the nail. The string is inclined at an angle of 60o to the wall. If the tension in the string is 4N, what is the effective force used in pulling the nail?
2√3 N
4 N
4√3 N
8 N
2 N
Explanation
F = 4 x sin 60o
F = 4 x √3/2 = 2√3 N
F = 4 x √3/2 = 2√3 N