🔍 Key Concepts

• Human body sensitivity to low-level electrical current (measured in milliamps, mA) • Difference between perception threshold (first painful shock) and let-go threshold (can’t release grip) • How increasing current changes effects: tingling → pain → muscle lock → possible fibrillation

💭 Think About

• Which answer range best represents the earliest level where most people would clearly feel a painful electric shock, not just a faint tingling? • Look at the higher values: at what point do currents start causing muscle control loss or serious injury, rather than just pain? • Compare the time component: does a short, low current match the question better than a higher current over a specified time?

✅ Before You Answer

• Focus on the lowest current range that is known to cause a clearly painful sensation in most people, not severe injury. • Ask: which options are more associated with involuntary muscle contraction and danger of fibrillation, rather than just initial pain? • Be sure the choice matches ‘minimum threshold’ and ‘painful sensation most people would perceive as a shock’, not the level where current becomes life-threatening.