In a chain drive system, the torque on the driven shaft will increase as the sprocket ratio increases.

• A. Decrease
• B. Increase
• C. Stay the same
• D. Vary unpredictably

Answer: (B)

Torque in a chain drive follows the same idea as a simple gear train: increasing the sprocket ratio provides greater mechanical advantage. When the driven sprocket has more teeth relative to the driver, the driven shaft turns more slowly but with more torque. Since power is roughly the same on both sides (minus losses), a higher output torque must accompany the reduced speed. In simple terms, the output torque is the input torque multiplied by the gear ratio (times efficiency), so as the ratio grows, the torque on the driven shaft grows as well. The other options don’t fit because they ignore the deterministic effect of gearing on torque or violate energy balance.