Question

Calculate the monthly and annual energy use (MJ) and the monthly and annual cost needed to fuel an automobile that is driven 1,000 miles each month at an average of 25 miles per gallon. The density of gasoline is about 0.7 that of liquid water and its heating value is 45,000 kJ/kg.

Answer 1

amount of gasoline required monthly = 40 gallon

amount of gasoline required annually = 480 gallon

monthly energy used = 4769.61 MJ

annually energy used = 57235.43 MJ

monthly cost is $2.653 × 40 = $106.12

annually cost = $2.653 × 480 = $1273.44

Step-by-step explanation:

given data

distance = 1000 moles / month = 12000 /annual

average consumption = 25 miles/gallon

density of gasoline = 0.7 of water density = 700 kg/m³

water density = 1000 kg/m³ and 1 m³ = 264.172 gallon

heating value = 45000 kJ/kg

heating value = 45000 × 700 ×
`(1)/(264.172)` = 119240.49 kJ/gallon

to find out

monthly and annual energy use (MJ) and the monthly and annual cost needed to fuel

solution

we find gasoline required per month that i s

amount of gasoline required = distance × average consumption

amount of gasoline required = 1000 ×
`(1)/(25)`

amount of gasoline required monthly = 40 gallon

and gasoline required annually

amount of gasoline required = 12000 ×
`(1)/(25)`

amount of gasoline required annually = 480 gallon

and

monthly energy used = heating value × gasoline required monthly

monthly energy used = 119240.49 × 40

monthly energy used = 4769.61 MJ

and

annually energy used = 119240.49 × 480

annually energy used = 57235.43 MJ

and we consider gasoline price is approx $2.653 / gallon

so

monthly cost is $2.653 × 40 = $106.12

annually cost = $2.653 × 480 = $1273.44