Answer the following question given this paragraph: 

Materials that eject electrons when illuminated with light, such as potassium, are called photoemissive. Not all materials are photoemissive, nor are all light sources capable of initiating electron emission from a given substance. For example, in Figure above , we see that 700 nm light will not initiate electron ejection, while 550 nm light will.


Q: What are materials that eject electrons when illuminated with light called?


A:
photoemissive