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girlinterrupt
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Hi,
Can someone please check my answers and possibly help with part c; I don't know where to begin on solving it.
A 31000kg jet airliner is flying at 11000m doing 910 km/h.
(a) What is the jet’s gravitational potential energy (GPE) at 11000m? (GPE=0 at sea level)
(b) What is the jet’s kinetic energy (KE)?
(c) If the jet fuel used contains 30.3MJ of energy per litre and the jet engines are 30% efficient at converting the fuel’s
energy, how much fuel is used just to raise the jet’s potential from sea level to 11000m
What is known:
m= 31000kg
h= 11000m
g=9.8m/s
v = 910km/h
e = 30.3 MJ/L
Answer:
a)
Gravitational Potential Energy:
U = mgh
U = 31000 x 9.8 x 11000
U = 3341800000 J = 3.3 x 10^9 J
b)
K = 1/2 mv^2
K = 1/2 31000 x 910000^2
K = 12835550000000000 = 1 x 1016 J
c) I have no idea where to start with this one!
Thanks, any help is greatly appreciated!
Can someone please check my answers and possibly help with part c; I don't know where to begin on solving it.
Homework Statement
A 31000kg jet airliner is flying at 11000m doing 910 km/h.
(a) What is the jet’s gravitational potential energy (GPE) at 11000m? (GPE=0 at sea level)
(b) What is the jet’s kinetic energy (KE)?
(c) If the jet fuel used contains 30.3MJ of energy per litre and the jet engines are 30% efficient at converting the fuel’s
energy, how much fuel is used just to raise the jet’s potential from sea level to 11000m
The Attempt at a Solution
What is known:
m= 31000kg
h= 11000m
g=9.8m/s
v = 910km/h
e = 30.3 MJ/L
Answer:
a)
Gravitational Potential Energy:
U = mgh
U = 31000 x 9.8 x 11000
U = 3341800000 J = 3.3 x 10^9 J
b)
K = 1/2 mv^2
K = 1/2 31000 x 910000^2
K = 12835550000000000 = 1 x 1016 J
c) I have no idea where to start with this one!
Thanks, any help is greatly appreciated!