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5.work,energy,power and collision — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics5.work,energy,power and collision1 Mark
MCQ
A $2\ kg$ object is floating at rest, acted upon by only force as indicated in figure. Find the total work done by the force in $3\ sec$ ..................... $\mathrm{J}$
  • A
    $10$
  • B
    $5$
  • ✓
    $25$
  • D
    $20$
✓

Answer

Correct option: C.
$25$
c
Area $=\mathrm{m}\left[\mathrm{v}_{f}-\mathrm{v}_{\mathrm{i}}\right]$

$20-10=2\left[v_{t}-0\right], v_{f}=5$

$\mathrm{W}=\frac{1}{2} \mathrm{m}\left[\mathrm{v}_{0}^{2}-\mathrm{v}_{1}^{2}\right]$

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