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How can a force be perpendicular to a point?! Surely you wanted to ask "Why no work is done when force is perpendicular to the direction of the displacement of the body?". This finds a simple answer in the definition of work: work done by a force F is defined as
W := ∫ Fdr,
where r is the position of the particle (that is, of the point of the body the force acts on), and hence dr is the direction of the displacement of the particle. From the definition, you immediatly see that if the angle between F and dris 90° (or, in general, (2n + 1)π/2, with n element of Z) the scalar product is Fdr = 0, and thus W = ∫0 = 0.
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What should be the angle between the direction of force and the direction of motion of a body so that the work done is zero?
If the force is perpendicular (at 90 degrees) to the direction of motion, that force does no work.
When force is perpendicular to the direction of motion is work done?
No. At least not by the force that's perpendicular to the motion. When you push a baby stroller (or a car), you do work, but the force of gravity, downward and perpendicular to the motion, doesn't.
Can a centripetal force ever do work on an object. explain?
Centripetal force refers to the force that acts on a body moving in a circular path. It does not do work on an object because it acts perpendicular to the motion of the body. The work done on a rotating object is zero.
What is the definition of the word 'work' in physics?
The word 'work' in physics is defined as the transfer of energy from one material body to another. It is a body's displacement in space caused by an external force resulting in motion. If a force is applied but there is no displacement or motion, then no work is done. Also work is not done if a force is applied perpendicular to the body's displacement. Work is expressed in units such as joules or foot-pounds.
Differentiate batween the work done on the body and work done by the body?
note: Work done is = force applied to a body * time taken by the body When we apply a force on to an object such that the object displaced in the direction of force, then some unit of work is done on the body. When a body sets another body into motion by applying a force, in unit time, that body is considered as it had done a unit of work
What is present when work is done?
In physics work is dome when a force acts on a body and the body moves in the direction of the force.
When body moves in a circular path how much work is done by the body?
Zero. This is because when a body when around in a circle, a centripetal force acts on the particle to keep it at that fixed distance from the centre. At each point, the force and the displacement are perpendicular to each other. Hence no work is done. The answer is NOT Zero! A Force is required in the direction of motion around the circle. At every point (an infinite number of them) there must be a Force PERPENDICULAR to the Centrifugal and Centripetal Forces or the object would not move. Therefore the amount of work done is the product of that FORCE times the circumference of the circular path, if only considering one revolution.
What is work done by a coolie walking on a horizontal platform with a load on his head?
The displacement of the load is perpendicular to the direction of force therefore work done by the coolie against the force of gravity is zero.
What should be the angle between the direction o foce and the direction of motion of a body so that the work done is zero?
Work is zero when the force is perpendicular to the direction of motion, as it is, for example, in a circular gravitational orbit.
What is defined work?
if the force applied on a body makes a body move that is there is a displacement of the point of application of force in the direction of force then work is said to be done by the body
Is it possible that a body be in accelarated motion under a force acting on a body yet no work is being done by the force?
Yes, that is possible. For example, an object in circular motion, accelerated towards the center. The force (and the acceleration) is normal (perpendicular) to the movement; thus, the dot product between the force and the displacement is zero.
Write the formula for the work done on a body when a force acts on the body in the direction of its displacement?
WORK = FORCE x DISPLACEMENT
