Figure "I" shown in the illustration is a diagram of a valve hand wheel, with S=5 inches and T=50 lbs. When an 18 inch cheater bar is used instead, and V=50 lbs., as shown in Figure "II", what value of additional torque is now being applied to the hand wheel valve stem? See illustration GS-0109.
• Torque = Force × Distance from the center of rotation • How adding a cheater bar changes the effective lever arm length • The question asks for additional torque compared to the original setup
• First, compute the original torque using the given 5 inch radius and 50 lb force. What is that value? • Next, determine the new effective lever arm length when the 18 inch cheater bar is added to the wheel radius, and use the same 50 lb force to find the new torque. • Finally, compare the two torque values: what is the ratio or difference, and which choice best matches the increase in torque?
• Be sure you convert all distances into the same units (e.g., inches) before calculating torque. • Confirm that you are using the distance from the valve stem center to the point where the 50 lb force is applied, not just the bar length alone. • Verify whether the answer choices are likely representing a multiplier (times original torque) rather than a raw torque value in in‑lb.
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