MCQ
When a conservative force does positive work on a body
- Athe potential energy increases
- ✓the potential energy decreases
- Ctotal energy increases
- Dtotal energy decreases
✓
Answer
Correct option: B.
the potential energy decreases
b
In conservative force $\vec{F}=\frac{-d V}{d r}$
In conservative force $\vec{F}=\frac{-d V}{d r}$
$=\vec{F} \cdot \overrightarrow{d r}=-d V$
$\int \vec{F} \cdot \vec{d} r=-\int d V$
When work done is positive. $d V$ is negative so potential energy decreases.
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