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a jet airplane travelling at the speed of 500 km h...

Question:
A jet airplane travelling at the speed of 500 km h^-1 ejects its products of combustion at the speed of 1500 km h^-1 relative to the jet plane. What is the speed of the latter with respect to an observer on ground?

Answer:

Speed of the jet airplane, v_jet = 500 km/h

Relative speed of its products of combustion with respect to the plane,

v_smoke = - 1500 km/h

Speed of its products of combustion with respect to the ground = v"²_smoke

Relative speed of its products of combustion with respect to the airplane,

v_smoke = v"²_smoke - v_jet

- 1500 = v"²_smoke - 500

v"²_smoke = - 1000 km/h

The negative sign indicates that the direction of its products of combustion is opposite to the direction of motion of the jet airplane.

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Question:
A jet airplane travelling at the speed of 500 km h^-1 ejects its products of combustion at the speed of 1500 km h^-1 relative to the jet plane. What is the speed of the latter with respect to an observer on ground?

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Question: A jet airplane travelling at the speed of 500 km h-1 ejects its products of combustion at the speed of 1500 km h-1 relative to the jet plane. What is the speed of the latter with respect to an observer on ground?

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Question:
A jet airplane travelling at the speed of 500 km h^-1 ejects its products of combustion at the speed of 1500 km h^-1 relative to the jet plane. What is the speed of the latter with respect to an observer on ground?