Energy of a photon : E = hf The photoelectric effect works like this. If you shine light of high enough energy on to a metal, electrons will be emitted from the metal. Light below a certain threshold frequency, no matter how intense, will not cause any electrons to be emitted.
The Boogie Board Jot 8.5 is an uber-slim slate with a black 8.5â³ screen. The stylus clicks into the opening under the screen. When you use the stylus it writes on the screen in a bright green color. The company claims this board is 50% brighter than their previous Jot model.
The DJI Mavic Pro (å¾¡) is a compact drone (UAV) that DJI introduced on September 27, 2016. It features multiple redundant sensors and obstacle avoidance to help prevent crashes. It has a foldable design that allows the drone to be transported more easily, similar to the GoPro Karma.