Question
Define power. State two mathematical expressions for power.
✓
Answer
The rate of doing work is called power.
$P=\frac{W}{t}=\frac{\overrightarrow{F} \times \overrightarrow{S}}{t}.........(1)$
$P=\overrightarrow{F} \cdot \vec{V}........(2)$
where,
$W \rightarrow$ Work done; $t \rightarrow$ Time; $V \rightarrow$ Velocity; $F \rightarrow$ Force
$P=\frac{W}{t}=\frac{\overrightarrow{F} \times \overrightarrow{S}}{t}.........(1)$
$P=\overrightarrow{F} \cdot \vec{V}........(2)$
where,
$W \rightarrow$ Work done; $t \rightarrow$ Time; $V \rightarrow$ Velocity; $F \rightarrow$ Force
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