o Torque is vector quantity . o o
The moment of a force vanishes if either The magnitude of the force is zero , or o The line of action of the force ( r sinΘ ) passes through the axis .
Example : Determine the torque on a bolt , if you are pulling with a force F directed perpendicular to a wrench of length l cm ?
Solution : t = r x F = rF sinΘ In this case Θ = 90 o
o
The quantity angular momentum is the rotational analogue of linear momentum .
o It could also be referred to as moment of ( linear ) momentum . o l = r × p