Bypass ratio the velocity of a very large volume and consequently mass of air produces a very large change in momentum and thrust: thrust is the engine's mass flow (the amount of air flowing through the engine) multiplied by the difference between the inlet and exhaust velocities in—a linear relationship—but the kinetic energy of the exhaust is the mass flow multiplied by one-half the square of the difference in velocities. A low disc loading (thrust per disc area) increases the aircraft's energy efficiency, and this reduces the fuel use. The Rolls–Royce Conway turbofan engine, developed in the early 1950s, was an early
Mercy Multiplied three financial principles for the program: According to the three guiding principles that founder Nancy Alcorn established, the Mercy Multiplied website states that they do not accept government funding, and as such, are supported solely by donations from individuals, organizations and other ministries. With regard to fund raising events, Mercy Multiplied host gala dinners, Christmas donation drives and running marathons throughout the year, and invite visitors to their website to donate by becoming a financial partner or "sponsoring" a girl. Mercy Multiplied also sell resources to raise funds such as books and sermons by founder Nancy Alcorn, as well as