Question

question 22 of 29
your washer has power of 400 watts, and your dryer has a power of 2200 watts. how much energy do you use to clean a load of clothes in 45 minutes of washing and 1 hour of drying?

a. 2.73×10³ j
b. 9.00×10⁶ j
c. 1.50×10³ j
d. 1.64×10⁷ j

Explanation:

Step1: Convert time to seconds

Washing time $t_1 = 45\ min=45\times60\ s = 2700\ s$, drying time $t_2=1\ h = 3600\ s$.

Step2: Calculate energy used for washing

The power of the washer $P_1 = 400\ W$. Using the formula $E = P\times t$, the energy used for washing $E_1=P_1t_1=400\times2700\ J = 1.08\times 10^{6}\ J$.

Step3: Calculate energy used for drying

The power of the dryer $P_2 = 2200\ W$. Using the formula $E = P\times t$, the energy used for drying $E_2=P_2t_2=2200\times3600\ J=7.92\times 10^{6}\ J$.

Step4: Calculate total energy

The total energy $E = E_1 + E_2=1.08\times 10^{6}+7.92\times 10^{6}\ J=9.00\times 10^{6}\ J$.

Answer:

B. $9.00\times 10^{6}\ J$