Certain force acting on a \(20\) \(kg\) mass changes its velocity from \(5\) \(m s^{–1}\) to \(2\) \(m s^{–1}\). Calculate the work done by the force.
Solution and Explanation
Work done by the force = change in kinetic energy
= \(\frac{1 }{ 2} \times m (v^2_1 - v^2_2)\)
= \(\frac{1 }{ 2} \times 20 \times (5^2 - 2^2)\)
= \(10 \times (25 - 4)\)
= \(10 \times 21\)
= \(210\) \(J\).
Top Questions on Work
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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.