The figure above shows 4 forces 3N 10N 3 3N and... - JAMB Physics 2007 Question

Resolution of force:

Total vertical upward force:

= 3√3 + 10 cos 60^o

= 3√3 + 5.

Total downward force

= 6 cos 30^o

= 6 x √(³/₂) = 3√3

Total horizontal forces towards right;

= 3N + cos 30^o

= 3N + 10 x √(³/₂)

= 3N + 5√3

Total horizontal forces towards left:

= 6 cos 60^o

= 6 x 0.5

= 3.0N
Summary:

Vertical resultant forces upward:

= 3√3 + 5 - 3√3

= 5N

Horizontal resultant forces towards right:

= 3N + 5√3 - 3√3

= 5N

Horizontal resultant force towards right

= 3N + 5√3 - 3N

= 5√3N

∴ R² = 5² + (5√3)²

= 25 + 25 x 3

= 100

∴ R = √100

= 10N