Question

During each hour of flight, a large jet airplane consumes 3330 gallons of fuel via combustion. Combustion releases 1.25 × 10⁶ joules/gallon. One gallon of fuel has a mass of 2.84 kg. Calculate the energy equivalent of 3330 gallons of fuel and determine the ratio (in percent) of this energy equivalent to the amount of energy released by combustion in one hour of flight.

1)	6.75 × 10–9 %

2)	7.63 × 10–6 %

3)	1.20 × 10–7 %

4)	2.42 × 10–8 %

5)	4.89 × 10–10 %

Answer 1

E=Eo/(undrt(1-v^2/c^2)

E1=4162.5*10^6 /(1-v^2/c^2)

E2=mc^2/undrt(1-v^2/c^2)

E2=2.84*9*10^16/undrt(1-v^2/c^2)

E2=25.56*10^8/undrt(1-v^2/c^2)

now for 1 hours flight =25.56*10^8*3600 sec/undrt(1-v^2.c^2)

=92016*10^8/undrt(1-v^2/c^2)

=9.2*10^12/undrt(1-v2/c^2)

the ratio (in percent) of this energy equivalent to the amount of energy released by combustion in one hour of flight.

now E1/E2=4162.5*10^6 /(1-v^2/c^2)/9.2*10^12/undrt(1-v2/c^2)

E1/E2=472.44*10^-6

E1/E2=4.72*10^-10 % answer is 5th