Question

The energy used by an appliance which operates at 240 volts at 15 amp for 4 hr. is A. 0.92 kwhr. B. 3.45 kwhr. C. 14.4 kwhr. D. 60.0 kwhr

Answer 1

C. 14.4 kwhr.

Step-by-step explanation:

To calculate the energy used by appliance first calculate the power. The formulae for calculating power(P) is
`P= I * V`, where V stands for voltage and I stands for current.

In the given problem, V = 240 volts and I = 15 amp. Therefore,

`P=240 * 15 =3600\ watt(w) = 3.6\ kw`

Now, formulae for calculating energy used i.e. work(W) is
`W = P* t`, where t is the time.

In the given question time is 4 hr. Therefore energy used will be,

Energy used (W) =
`3.6*4 =14.4\ kwhr`.