What term is used for the ratio where output speed equals input speed, resulting in no net speed change?

What term is used for the ratio where output speed equals input speed, resulting in no net speed change?

• A. Underdrive
• B. Overdrive
• C. Direct drive
• D. Reverse

Answer: (C)

Direct drive is the 1:1 ratio where the output speed matches the input speed, so there’s no net speed change as power is transmitted (aside from small losses from friction and inefficiencies). In this setup, the gears are arranged so the input shaft and output shaft rotate at the same rate. Underdrive would slow the output relative to the input (less than 1:1), and overdrive would speed it up (greater than 1:1). Reverse changes the rotation direction rather than keeping the same speed.

Direct drive is the 1:1 ratio where the output speed matches the input speed, so there’s no net speed change as power is transmitted (aside from small losses from friction and inefficiencies). In this setup, the gears are arranged so the input shaft and output shaft rotate at the same rate.

Underdrive would slow the output relative to the input (less than 1:1), and overdrive would speed it up (greater than 1:1). Reverse changes the rotation direction rather than keeping the same speed.