In negative logic, which statement about voltage levels is true?

In negative logic, which statement about voltage levels is true?

• A. High represents 1; Low represents 0
• B. High represents 1; Low represents 1
• C. High represents 0; Low represents 0
• D. High represents 0; Low represents 1

Answer: (D)

In negative logic, the voltage level that represents a logical true or asserted condition is inverted compared with positive logic. A low voltage (near ground) is treated as a 1, while a high voltage (near the supply) is treated as a 0. So the statement “High represents 0; Low represents 1” correctly describes negative logic. This is common in active-low signals, where devices are considered active when the line is pulled low. The other possibilities would either map high to 1 and low to 0 (positive logic), assign the same value to both levels, or assign no meaningful binary distinction, which isn’t consistent with binary encoding.

In negative logic, the voltage level that represents a logical true or asserted condition is inverted compared with positive logic. A low voltage (near ground) is treated as a 1, while a high voltage (near the supply) is treated as a 0. So the statement “High represents 0; Low represents 1” correctly describes negative logic. This is common in active-low signals, where devices are considered active when the line is pulled low. The other possibilities would either map high to 1 and low to 0 (positive logic), assign the same value to both levels, or assign no meaningful binary distinction, which isn’t consistent with binary encoding.