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

Gujarat BoardEnglish MediumSTD 11 SciencePhysics5.work,energy,power and collision1 Mark
MCQ
How much work does a pulling force of $40 \,N$ do on the $20\, kg$ box in pulling it $8 \,m $ across the floor at a constant speed. The pulling force is directed at $60^o $ above the horizontal.....$J$
  • ✓
    $160 $
  • B
    $277$
  • C
    $784 $
  • D
    None of the above
✓

Answer

Correct option: A.
$160 $
a
(a) $W = \vec F.\vec s = 40 \times 8 \times \cos 60^\circ = 160\,J$

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