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:-
• AUTOZERO ON
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.
• AUTOZERO 0FF
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.