The primary coil of a transformer has 180 turns more than the number of turns of the secondary coil. An output voltage of 18v is obtained when the input voltage is 45v. Calculate the number of turns in the secondary coil.

An important dimensionless parameter concerned with very high-speed flow is the mach number, defined as v/c, where v is the speed of the object such as an airplane or projectile, and c is the speed of sound in the fluid surrounding the object. for a projectile traveling at 1170 mph through air at 50 ˚f and standard atmospheric pressure, what is the value of the mach number?