Final answer:
Crown gear backlash is measured using a dial indicator, which allows for precise clearance readings between mated gear teeth. When additional force is applied to gear A, causing increased torque, gear B's angular velocity generally increases in magnitude.
Step-by-step explanation:
To measure crown gear backlash, option A, With a dial indicator, is used. Backlash in gears is the amount of clearance between mated gear teeth. It's crucial for allowing for thermal expansion and preventing teeth from binding. To measure backlash, you would set up the dial indicator so that its plunger is in contact with a tooth on the crown gear. As you rock the gear back and forth, you'd watch the dial to see how much play there is between the gear teeth.
Answering the second part of the question regarding gear A and gear B, if more force is applied through gear A, causing increased torque, the angular velocity of gear B would typically increase in magnitude, assuming that the system can handle the increased load without slipping or other mechanical failure.