A jet plane is flying at 130 m/s relative to the ground. There is no wind. The engines take in 81 kg of air per second. Hot gas (burned fuel and air) is expelled from the engines at high speed. The engines provide a forward force on the plane of magnitude 6.0 × 104 N. At what speed relative to the ground is the gas being expelled?
[Look at the momentum change of the air taken in by the engines during a time interval Δ t.] This calculation is approximate since we are ignoring the 3.0 kg of fuel consumed and expelled with the air each second?