A force 2i + j has moves its point of application form (2,3) to (6,5). What is work done?
Correct answer: B. +10
- A. -10
- B. +10
- C. -18
- D. +18
Explanation
Work is a scalar quantity and work done is a dot product of force and displacement.The difference between the two pints will be our distance.d =(6i+5j)-(2i+3j)d=6i-2i+5j-3jd=4i+2jIf we apply force and there will be displacement then it is called work.wd = f . dW=(2i+j).(4i+2j)W=2x4 + 1x2W =8+2W =+10J
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About Work
Work is done when a force produces displacement, with its value determined by the component of force along the displacement. The topic covers positive, negative and zero work, work by variable forces from force-displacement graphs, and the connection between net work and change in kinetic energy.
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