Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.
Solution and Explanation
According to Newton's first law of motion, an object will remain at rest or in uniform motion unless acted upon by a net external force. In the absence of any external force, an object at rest will stay at rest, and an object in motion will continue moving at a constant velocity. However, internal forces like friction or air resistance could still cause displacement.
So, while external forces are necessary for changes in motion, internal forces can lead to displacement even without an external force.
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Use these adverbs to fill in the blanks in the sentences below.
awfully sorrowfully completely loftily carefully differently quickly nonchalantly(i) The report must be read ________ so that performance can be improved.
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(iv) The teacher shook her head ________ when Ravi lied to her.
(v) I ________ forgot about it.
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Concepts Used:
Work
Work is the product of the component of the force in the direction of the displacement and the magnitude of this displacement.
Work Formula:
W = Force × Distance
Where,
Work (W) is equal to the force (f) time the distance.
Work Equations:
W = F d Cos θ
Where,
W = Amount of work, F = Vector of force, D = Magnitude of displacement, and θ = Angle between the vector of force and vector of displacement.
Unit of Work:
The SI unit for the work is the joule (J), and it is defined as the work done by a force of 1 Newton in moving an object for a distance of one unit meter in the direction of the force.
Work formula is used to measure the amount of work done, force, or displacement in any maths or real-life problem. It is written as in Newton meter or Nm.