What is hystersis of instrument?

Answer 1

Generally, it will be considered the "interval" between action and response. For example, if a radio transceiver operates at 800 MHz, it may receive at 800 MHz +/- 0.005 MHz and transmit at 801 MHz. The interval is the hysteresis. Looking at a pH meter during an acid-base titration. As you add buffer or your titre, you don't see an immediate response. The "lag-time" of the addition of buffer could also be considered the hysteresis for that instrument in that system. An instrument any instrument will have an ambiguity of resolution at the low end it cannot display half a value it is either this or that decision therefore hysteresis