Which of the following is not correct for the condition for work not t...
There are two conditions for zero work done after applying force physically:
1. If the displacement is zero whether how much force is applied on the object in this case work done will be zero Example . If you will push the wall of house with much force so in this case your work done count will be zero.
2. As, W=Fd cosx where x is the angle between force and displacement; if the angle is 90 i.e force and displacement are perpendicular to each other, then W = 0.
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Which of the following is not correct for the condition for work not t...
If a force acting on a body has a component in the direction of displacement, then the work done by the force is positive. Hence when a body falls freely under the influence of gravity the work done by the gravity is positive.
Which of the following is not correct for the condition for work not t...
Explanation:
The condition for work not to be done is when either the force or the displacement is zero. In other words, work is not done when there is no force acting on an object or when there is no displacement of the object.
Let's analyze each option to determine which one is not correct:
a) Force and displacement are perpendicular to each other:
When a force acts on an object and the displacement is perpendicular to the force, work is still done. The work done in this case is given by the formula: Work = force * displacement * cos(theta), where theta is the angle between the force and the displacement vectors. Since cos(90 degrees) = 0, the work done would be zero only if either the force or the displacement is zero. Therefore, option 'a' is not the correct answer.
b) Force and displacement are at 180 degrees with each other:
When the force and displacement are in opposite directions (180 degrees apart), work is indeed done. The work done in this case is given by the formula: Work = force * displacement * cos(theta), where theta is the angle between the force and the displacement vectors. Since cos(180 degrees) = -1, the work done would be negative. Therefore, option 'b' is the correct answer.
c) Displacement is zero, though force is non-zero:
If the displacement of an object is zero, it means that the object is not moving. In this case, no work is done even if there is a non-zero force acting on the object. Therefore, option 'c' is not the correct answer.
d) Force is zero:
If there is no force acting on an object, no work is done regardless of the displacement. Therefore, option 'd' is a correct condition for work not to be done.
Conclusion:
The correct answer is option 'B' because work is done when the force and displacement are at 180 degrees with each other.
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