A particle experiences a variable force $\overrightarrow F = \left( {4x\widehat i + 3{y^2}\widehat j} \right)$ in a horizontal x-y plane. Assume distance in meters and force is newton. If the particle moves from point (1, 2) to point (2, 3) in the x-y plane, then Kinetic Energy changes by :
Solution
<p>$W = \int {\overrightarrow F \,.\,d\overrightarrow r }$</p>
<p>$= \int\limits_1^2 {4xdx + \int\limits_2^3 {3{y^2}dy} }$</p>
<p>$= [2{x^2}]_1^2 + [{y^3}]_2^3$</p>
<p>$= 2 \times 3 + (27 - 8)$</p>
<p>$= 25$ J</p>
About this question
Subject: Physics · Chapter: Work, Energy and Power · Topic: Work Done by a Force
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