(7A10.10) Photoelectric Effect
A zinc plate is attached to an electroscope. Negatively charge the zinc plate using the PVC pipe. Using the flood lamp and other light sources show that only the 254 nm light source is able to excite the electrons on the zinc plate and discharge it. Using the glass tube positively charge the zinc plate and shows that nothing happens no matter the light source because the zinc plate has been stripped of electrons.