AIIMS2013PhysicsRotational Motion
Given that force (5 i +7 j -3 k ) N acts on a particle at position ( i + j - k ) m . Find torque of this force on the particle about origin.
Options
- A4 i -2 j +2 k
- B2 i -3 j +4 k
- C5 i -2 j +3 k
- D6 i -4 j +4 k
Correct answer
A. 4 i -2 j +2 k
Step-by-step solution
Torque, = r F =( i + j - k ) (5 i +7 j -3 k )= i (-3+7)- j (-3+5)+ k (7-5) =4 i -2 j +2 k