Question

How long does it take a microwave of power 0.2kW to sue 10000 J of energy

Answer 1

50s .

Step-by-step explanation:

`\frak{\pink{Given}}\begin{cases}\textsf{ The power of microvave is 0.2kW .}\\\textsf{ Amount of energy is 10000 J .}\end{cases}`

Here the power of the microwave is 0.2kW . And as we know that ,

• Rate of doing work is called power .

So from the definition , we have ;

`\sf\longrightarrow Power =(Work)/(time)`

• Here the work done is equal to the energy consumed by the microwave i.e. 10000 J .So we can write it as ,

`\sf\longrightarrow Power =(Energy)/(time)`

`\sf\longrightarrow 0.2kW = (10^4 J )/(t) \\`

`\sf\longrightarrow 0.2 * 1000 W = (10^4 J )/(t)`

Cross multiply ,

`\sf\longrightarrow t = ( 10^4 )/( 0.2 * 10^3)s=(10^4)/(2*10^2) s`

Simplify ,

`\sf\longrightarrow \boxed{\bf t = 50s}`

Hence the time taken is 50s .