🔍 Key Concepts

• Basic operation of a vacuum tube or thermionic valve (emitter/cathode and plate/anode) • What happens to electrons in the space between the emitter and the plate when the plate voltage is not high enough • Distinctions between space charge, plate saturation, and getter in electronic components

💭 Think About

• Think about where extra electrons would physically accumulate if the plate cannot attract all of them. What is that region called? • Ask yourself: which term describes a cloud or region of electric charge, and which terms instead refer to a component or a condition of maximum current? • Consider which option is an actual electrical effect in the tube versus a device or a limiting condition.

✅ Before You Answer

• Identify which choice refers to a physical component inside a vacuum tube (not the effect being described). • Determine which term is associated with a cloud of electrons near the cathode/emitter when the anode voltage is insufficient. • Verify which term describes a limit of plate current rather than the actual accumulation of charge itself.