Question #032b6

1 Answer
May 27, 2016

The net force is the vector sum of all the forces acting on an object.

Explanation:

Whenever a number of forces act on an object, and if the vector sum of all the forces is not balanced, then we have a resultant force. This is called net force. A net force is capable of accelerating a mass. The acceleration could be linear or circular or both.

In equilibrium state net force acting on an object is zero. The object does not accelerate.

In the figure below force #vec F# acts at a point H of a free rigid body. The body has the mass #m# with its center of mass at point C.
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The net force causes changes in the motion of the object described by the following expressions.

  1. Linear acceleration of center of mass #vec a = vec F/ m#;
    where #vecF# is the Net Force and #m# is mass of the object
  2. Angular acceleration of the body #vec alpha = vec tau / I#,
    where #vectau# is the resultant torque and #I# moment of inertia of the body.
    Torque, a vector quantity is caused by a net force #vec F# defined with respect to some reference point #vecr# as below
    #\vec \tau = \vec r \times \vec F#
    or #|\vec \tau |= k |\vec F|#