Under which condition will a ground be provided for the warning horn through both gear switches when the throttles are closed?

Under which condition will a ground be provided for the warning horn through both gear switches when the throttles are closed?

• A. Right gear up and left gear down
• B. Left gear up and right gear down
• C. Gears up and throttles retarded
• D. Gears down and throttles closed

Answer: (B)

The key idea is that the warning horn is grounded through two gear-position switches that are in series. Each switch closes only when its corresponding condition is met: a switch on the left gear closes when the left gear is up, and a switch on the right gear closes when the right gear is down. For current to flow and energize the horn with throttles closed, both switches must be closed, meaning one gear is up and the other is down. With throttles closed, the circuit completes only when one gear is up and the other gear is down. That makes the combination of left gear up and right gear down the condition that provides the ground path through both gear switches, triggering the warning horn. If the gears were both down or both up, one of the switches would be open and the path would not be complete; if the opposite pairing were used, the wiring arrangement wouldn’t provide the required series path in this setup.

The key idea is that the warning horn is grounded through two gear-position switches that are in series. Each switch closes only when its corresponding condition is met: a switch on the left gear closes when the left gear is up, and a switch on the right gear closes when the right gear is down. For current to flow and energize the horn with throttles closed, both switches must be closed, meaning one gear is up and the other is down.

With throttles closed, the circuit completes only when one gear is up and the other gear is down. That makes the combination of left gear up and right gear down the condition that provides the ground path through both gear switches, triggering the warning horn. If the gears were both down or both up, one of the switches would be open and the path would not be complete; if the opposite pairing were used, the wiring arrangement wouldn’t provide the required series path in this setup.