The circumference of the earth is almost 25,000 miles. Mach 5 is roughly 3802.79 mph, therefore it would take about six and a half hours to travel the earth's circumference. This is assuming a constant speed of Mach 5 would be maintained and the jet in question did not have to stop and refuel.
About 37 hours 20 minutes.
The cruising speed of the Concorde was mach 2.04, or about 1552 miles per hour. Assuming that you are referring to a non-stop flight around the equator, it would take a Concorde about 16 hours to fly around the world at that speed, ignoring weather, actual range, and the rotation of the Earth.
8000 mph would be mach 10.42.
Mach 3.5 is about 2,595.4 mph
The speed of sound is around 760 miles per hour = Mach 1. So Mach 4 is 4*760 = 3040 mph.
The SR71 blackbird flies at around 3535 km per hour which is close to mach 3 (3 times the speed of sound). The peed of sound is 1193.04 km per hour. The circumfrence of the earth along the equator is about 40,075.16 km. Divide the distance of the earth and mach 3 and you should get an answer of around 11 hours and 30 min. Note that it may vary in the real world due to temperature, altitude, gas breaks, etc.
60 minutes (4x15minute quarters)
It depends on how fast they are flying. At mach 1 it would take an hour and a half.
The Mach number for speed is a function of how fast an object is going relative to the speed of sound in that medium (which can vary). The speed of sound at sea level is around 768 mph, so Mach 3.3 at around this level will be 768 x 3.3 = 2534 mph
Mach refers to the speed of sound, for example, mach 1, equals the speed of sound, mach 2, the speed of sound times 2. So, mach 25 would mean, 25 times the speed of sound.
0.96 mach is 96% the speed of sound. Mach 96 would be 96 times the speed of sound.
60 minutes (4x15minute quarters)