The best form of coupling is _____ A. complete B. tight C. loose D. free

The best form of coupling is complete. A complete coupling is one in which the two shafts are aligned and the coupling is able to transmit the full torque from one shaft to the other. A tight coupling is one that is difficult to separate, but it may not

be able to transmit the full torque if the shafts are not aligned. A loose coupling is one that is easy to separate, but it may not be able to transmit any torque if the shafts are not aligned. A free coupling is one that allows the shafts to rotate independently of each other, and it cannot transmit any torque.

A complete coupling is the best form of coupling because it provides the most efficient transmission

of power from one shaft to the other. A tight coupling may be able to transmit more power than a loose coupling, but it is more difficult to install and remove. A free coupling is not useful for transmitting power, but it may be useful for allowing two shafts to rotate at different speeds.