4. (a) What is the importance of a radial magnetic field and how is it produced?
(b) Why is it that while using a moving coil galvanometer as a voltmeter a high resistance in
series is required whereas in an ammeter a shunt is used?
Plz.... answer fast I will mark ur answer as brainliest answer....
Answers
Explanation:
It is produced due to cylindrical pole pieces and soft iron core. (ii) Voltmeter : A high resistance in series is required when moving coil galvanometer is used as voltmeter to make sure that a low current should travel through voltmeter without changing the potential difference that needs to be measured.
Answer:
Explanation:
A- Radial field is used to produce a constant torque in the coil, which makes the deflection angle directly proportional to the current.
uses- it is used to make the plane of the loop(coil) perpendicular to the magnetic field.
B- We use high resistance in voltmeter beacuse initially, the resistance decreases the potential difference across the conductor, so we need to connect a resistor with really high resistance.
On the other hand, in ammeter. initially, the resistance decreases the current acroos the conductor, so we need the attach a resistor ith resistance nearly equal to ZERO(as shunt has nearly zero resistance in it.)