MCQ
A force $\vec F = (5\hat i + 3\hat j + 2\hat k)N$ is applied over a particle which displaces it from its origin to the point $\vec r = (2\hat i - \hat j)m$. The work done on the particle in joules is
- A$-7$
- ✓$+7$
- C$+10$
- D$+13$
✓
Answer
Correct option: B.
$+7$
b
(b)$W = \overrightarrow F .\overrightarrow r = (5\hat i + 3\hat j + 2\hat k).(2\hat i - \hat j) = 10 - 3 = 7\,J$
(b)$W = \overrightarrow F .\overrightarrow r = (5\hat i + 3\hat j + 2\hat k).(2\hat i - \hat j) = 10 - 3 = 7\,J$
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