With reference to Ramjet, consider the following statements:1.It is a type of jet engine that takes up oxygen from the atmosphere during flight.2.Efficiency of Ramjet begins to drop at hypersonic speeds.Which of the statements given above is/are correct?

[A] 1 only

[B] 2 only

[C] Both 1 and 2

[D] Neither 1 nor 2

Answer: C

Notes:

Both statements are correct.

A ramjet is a form of air-breathing jet engine that takes up oxygen from the atmosphere during flight. Thus, it doesn’t require an oxidizer as part of the solid motor.
However, ramjet-powered vehicles require an assisted take-off like a rocket. It assists to accelerate it to a speed where it begins to produce thrust.
Further, ramjets work efficiently at supersonic speeds around Mach 3 (three times the speed of sound) and can operate up to speeds of Mach 6. But the ramjet efficiency starts to drop when the vehicle reaches hypersonic speeds.

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