A typical outdoor porch light is rated at 40 Watts (W). How many kilowatt-hours (kWh) does...

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A typical outdoor porch light is rated at 40 Watts (W). How many kilowatt-hours (kWh) does a 40W porch light use in one day? (In 24 hours.) (b) How much would it cost to leave the porch light on for the entire month of September using the rates listed in Figure 1? (c) If your bill indicated you spent $10 on off-peak electricity (and nothing else), could you calculate how much energy (in kWh) you used? Does your ability to calculate your total energy usage change if your bill only listed a total dollar amount for all three usages rates? (d) Electricity rates in Ontario have decreased since the start of the pandemic (unlike in many other jurisdictions). On January 1, 2020, the off-peak rate was 12.8 cents/kWh and on May 1, 2022 the same tier is 8.2 cents/kWh. If we assume a continuous compounding model, the off-peak rate R(t) as a function of t months since January 1, 2020 is given by R(t)=Roe where R is the rate on January 1, 2020. Find an exact formula for R(t) = Reet by determining the values for Re and r. Answer in exact form (do not round any values). (e) Use your answer in (d) to compute the predicted off-peak electricity rate on January 1, 2025 and on January 1, 2035. Use a calculator to round your final answers to 2 decimal places. Based on your answers, comment briefly on whether this mathematical model for the cost of electricity seems suitable for long-term predictions. A typical outdoor porch light is rated at 40 Watts (W). How many kilowatt-hours (kWh) does a 40W porch light use in one day? (In 24 hours.) (b) How much would it cost to leave the porch light on for the entire month of September using the rates listed in Figure 1? (c) If your bill indicated you spent $10 on off-peak electricity (and nothing else), could you calculate how much energy (in kWh) you used? Does your ability to calculate your total energy usage change if your bill only listed a total dollar amount for all three usages rates? (d) Electricity rates in Ontario have decreased since the start of the pandemic (unlike in many other jurisdictions). On January 1, 2020, the off-peak rate was 12.8 cents/kWh and on May 1, 2022 the same tier is 8.2 cents/kWh. If we assume a continuous compounding model, the off-peak rate R(t) as a function of t months since January 1, 2020 is given by R(t)=Roe where R is the rate on January 1, 2020. Find an exact formula for R(t) = Reet by determining the values for Re and r. Answer in exact form (do not round any values). (e) Use your answer in (d) to compute the predicted off-peak electricity rate on January 1, 2025 and on January 1, 2035. Use a calculator to round your final answers to 2 decimal places. Based on your answers, comment briefly on whether this mathematical model for the cost of electricity seems suitable for long-term predictions.

Answer rating: 100% (QA)

a To calculate how many kilowatthours kWh a 40W porch light uses in one day 24 hours we can use the formula Energy kWh Power kW Time hours Since 1 kil... View the full answer