Calculate the energy consumed by 120W toaster in 20 min .
Hint: In order to answer this question we have to know about energy . To calculate the amount of energy we use this formula – Energy (E) \[= \] Power(P) \[\times \] time (t).
Complete answer: Energy is known as the product of work power and required time i.e. the capacity of work . From the above question we get , Power \[= 120watt\], AND time \[=20\min \] \[= 20\times 60s= 1200s\]
\[\therefore \] Energy (E) \[= 120\times 1200=144000J= 144KJ\]. Therefore the amount of energy consumed by toaster is \[144KJ\]
Note: Joule is the unit of energy and equal to the energy used in applying a power of one newton through a distance of one meter. The total system’s energy is conserved in a closed system according to the law of conservation of energy.