Due to efficiency considerations related to its bow wake, the supersonic transport aircraft must maintain a cruising speed that
is a constant ratio to the speed of sound (a constant Mach number). If the aircraft flies from warm air into colder air, should it increase or decrease its speed? Explain.
When the aircraft is flies from the warm air into the colder air then its speed will be decreases.
as we know that
we know mach number is constant
so that here Mach number M is expressed as
M = .............................1
here u is Local flow velocity with respect to the boundarie and v is the speed of sound in the medium
If the aircraft flies from hot air to cold air, the speed of sound in the medium will decrease. But the Mach number remains constant. Therefore, the local flow velocity relative to the boundaries also decreases.
Newton's first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force.