Advertisements
Advertisements
प्रश्न
Increasing the current sensitivity of a galvanometer may not necessarily increase its voltage sensitivity. Explain, giving reason.
Advertisements
उत्तर
The current sensitivity of a moving coil galvanometer is given by `(nBA)/k`, where n is the number of turns , A is the area of the coil , B is the magnetic field strength of the poles and k is the spring's constant of the suspension wire.
Similarly, voltage sensitivity is given by `(nBA)/(kR)`, where R is the resistance of the wire.
From the above two expressions, we get:
Voltage sensitivity = Current sensitivity/R
Thus, on increasing the current sensitivity, voltage sensitivity may or may not increase because of similar changes in the resistance of the coil, which may also increase due to increase in temperature.
APPEARS IN
संबंधित प्रश्न
Show that the current flowing through a moving coil galvanometer is directly proportional to the angle of deflection of coil.
A galvanometer has a resistance of 16Ω. It shows full scale deflection, when a current of 20 mA is passed through it. The only shunt resistance available is 0.06 which is not appropriate to convert a galvanometer into an ammeter. How much resistance should be connected in series with the coil of galvanometer, so that the range of ammeter is 8 A?
Define the current sensitivity of a galvanometer ?
Draw a labelled diagram of a moving coil galvanometer and explain its working. What is the function of radial magnetic field inside the coil?
What are the advantages of using soft iron as a core, instead of steel, in the coils of galvanometers?
In a moving coil galvanometer the deflection (Φ) on the scale by a pointer attached to the spring is ______.
Assertion (A): On Increasing the current sensitivity of a galvanometer by increasing the number of turns may not necessarily increase its voltage sensitivity.
Reason (R): The resistance of the coil of the galvanometer increases on increasing the number of turns.
Select the most appropriate answer from the options given below:
In the pivoted-coil (Weston) type galvanometer, the two hair springs:
A voltmeter is connected across a component:
