If
is the displacement vector of a particle moved from a point to another point after applying a constant force
on the particle, then the work done by the force on the particle is
If the force has an acute angle, perpendicular angle, and an obtuse angle, the work done by the force is positive, zero, and negative respectively.
If a force
is applied on a particle at a point with position vector
then the torque or moment on the particle is given by
The torque is called rotational force.
Problem 1 :
Forces of magnitudes 5√2 and 10√2 units acting in the directions
respectively act on a particle which is displaced from the point with position vector
to the point with position vector
Find the work done by the forces.
Solution :
Adding forces :
Difference between position vectors :
Work done :
Problem 2 :
Find the magnitude of the direction cosines of torque represented by
about the position vector
acting through the position vector is
Solution :
Finding magnitude :
Finding Direction Cosine :
Problem 3 :
Find the torque of the resultant of the three forces represented by
acting at the point with position vector
about the point with position vector
Solution :
Finding torque :
May 21, 24 08:51 PM
May 21, 24 08:51 AM
May 20, 24 10:45 PM