Forces proportional to `AB , BC` and `2 CA` act along the slides of a triangle `ABC` in magnitude and direction by

Options

A. CA
B. AC
C. BC
D. CB

Answer

A

Explanation

For triangle `ABC: vec(AB)+vec(BC)+vec(CA)=vec(0)`
Now `vec(AB)+vec(BC)+2vec(CA)`
`=vec(AB)+vec(BC)+vec(CA)+vec(CA)+vec(0)+vec(CA)=vec(CA)`