What does it mean if the net external force is equal to zero?

What does it mean if the net external force is equal to zero?

Equilibrium. • When an object is in equilibrium (either at rest or moving with constant velocity), the net force acting on it zero. A vector can only have zero magnitude if all of its components are zero.

What happens to an object if the external force is zero?

These three laws state: If an object experiences no net force, its velocity will remain constant. The object is either at rest and the velocity is zero, or it moves in a straight line with a constant speed.

Is it possible for the total work done on the object to be zero?

If an object is moving with a constant velocity, then by definition it has zero acceleration. So there is no net force acting on the object. The total work done on the object is thus 0 (that’s not to say that there isn’t work done by individual forces on the object, but the sum is 0 ).

Why is work done in a circle zero?

Work done on an object is the force applied and the displacement covered in the direction of the force applied. W=FScosθ. Force in uniform circular motion is always perpendicular to the displacement and hence the angle between F and S is 900 always. Hence, The work done in a uniform circular motion is always zero.

What is work done by an external force?

When work is done by external forces (nonconservative forces), the total mechanical energy of the object is altered. The work that is done can be positive work or negative work depending on whether the force doing the work is directed opposite the object’s motion or in the same direction as the object’s motion.

How much work do external forces perform?

Then, the work done by the external forces is zero, and the change in the total energy of the system is also zero. The diagram just shows an increase in kinetic energy at the expense of an equal decrease in potential energy.

Why has no work been done if there is no displacement?

No work has been done if there is no displacement because in the equation W=F x D, If D is zero, then W becomes zero. We measure work by whether or not motion has occurred, and motion has occurred if the object has been displaced, or has moved some distance.

How can work done be zero?

Zero work is done when the displacement of a body is zero or perpendicular (θ=900,cosθ=0) to the direction of force applied, then work done is zero. For example, if a person tries to push a wall, he is applying force yet the wall does not move, so the displacement of the wall is zero, and hence work done is zero.

Why is no work done by centripetal force?

So, work done by a centripetal force is always zero. As we found the centripetal force is the force applied due to centripetal acceleration and the force is not responsible for the displacement of the particle. So, the displacement is zero therefore the work done is also zero.

Why is the work done?

The purpose of this force is to move the body through a certain distance in a straight path in the direction of the force. Now, the total work done by this force is equal to the product of the magnitude of applied force and the distance traveled by the body.

When the work done is zero?

Work done is zero when the force is perpendicular to the displacement. It can also be zero if either the force or the displacement are zero. Work is a scalar quantity, similar to energy.

What happens when the displacement of an object is zero?

Or you can say when displacement of object is zero then work is zero (W=Force × displacement). If I carry an object A from place X to Y and carry it back to X, the displacement and work done will be zero in physics.

Is work done scalar or vector quantity?

Work is the scalar product of force and displacement vectors, F*s, where F is the force applied and s is the displacement. Work done is zero when the force is perpendicular to the displacement. It can also be zero if either the force or the displacement are zero. Work is a scalar quantity, similar to energy.

What happens when force is applied at the center of mass?

Recall that the CM has a special physical meaning: When an external force is applied to a body at exactly its CM, the body as a whole undergoes translational motion and such a force does not cause rotation. When the CM is located off the axis of rotation, a net gravitational torque occurs on an object.