Question

The energy required for an appliance to run is $100{\text{J s}}^{-1}$. What is the power consumed by it in $\text{W}$, if it operates at $220\text{V}$?

• A. $0.1\text{W}$
• B. $10\text{W}$
• C. $100\text{W}$
• D. $1000\text{W}$

Answer 1

The correct option is C $100\text{W}$

Energy consumed by the appliance is same as the work done. Since, power = work done per unit time.
So, energy per unit time or work done per unit time gives us the required power.
Since $1{\text{J s}}^{-1}=1\text{W}$,
$100{\text{J s}}^{-1}=100\text{W}$