COMEDK · Physics · 6. Work Power Energy
A \(2 \mathrm{~kg}\) mass lying on a table is displaced in the horizontal direction through \(50 \mathrm{~cm}\). The work done by the normal reaction will be
- A \(10 \mathrm{~J}\)
- B 0
- C \(100 \mathrm{erg}\)
- D \(100 \mathrm{~J}\)
Answer & Solution
Correct Answer
(B) 0
Step-by-step Solution
Detailed explanation
Since, displacement on the body of mass \(2 \mathrm{~kg}\) is in the horizontal direction while normal reaction acts on the body in perpendicular to the displacement. Hence, \(\quad \theta=0\) \(\therefore\) Work done, \(W=F s \cos 90^{\circ}=0\)
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