Ques-1: Differentiate between electrostatic deflection and electromagnetic deflection in cathode ray tube ?
ELECTROSTATIC DEFLECTION ELECTROMAGNETIC DEFLECTION
It is the method of aligning the path of charge particles by applying the electric field between the deflection plates. It is method of aligning the path of charge particles by applying the magnetic field externally between the deflection plates.
Electrostatic deflection uses the electric field to the charge particles. Electromagnetic deflection uses the magnetic field to the charged particles.
The amount of charge applied to the plates controls the amount of deflections. The amount of polarity and strength of external magnetic field controls the amount and direction of deflections.
Ques-2: Explain auto-zero mechanism in digital multimeter?
In measurement of time in digital multimeter then there is two condition appear which is as follows:-
The instrument internally disconnected the input signals and takes a zero reading. It then subtracted the zero reading to preceeding reading. This prevents offsets voltages reset on the instrument’s input circuitary from affecting measurement accuracy.
The instrument uses the last measured zero reading and subtracts it from each measurement . it takes a new zero reading each time you change the function, range, or intregration time.