Advertisements
Advertisements
Question
Define current sensitivity of a galvanometer.
Advertisements
Solution
Current sensitivity of a galvanometer is defined as the deflection produced in the galvanometer when a unit current flows through it.
θ = `("nBA")/"k""I"`
So, for a given value of I, θ will be large if `("nBA")/"k"` is large i.e n, B and A should be large and k should be small.
APPEARS IN
RELATED QUESTIONS
A rectangular coil of a moving coil galvanometer contains 50 turns each having area 12 cm2 . It is suspended in radial magnetic field 0.025 Wb/m2 by a fibre of twist constant 15 x10-10 Nm/degree. Calculate the sensitivity of the moving coil galvanometer.
Draw a labelled diagram of a moving coil galvanometer. Describe briefly its principle and working.
Two moving coil meters, M1 and M2 have the following particulars:
R1 = 10 Ω, N1 = 30,
A1 = 3.6 × 10–3 m2, B1 = 0.25 T
R2 = 14 Ω, N2 = 42,
A2 = 1.8 × 10–3 m2, B2 = 0.50 T
(The spring constants are identical for the two meters).
Determine the ratio of
- current sensitivity and
- voltage sensitivity of M2 and M1.
The current sensitivity of a galvanometer is defined as ______.
The coil of a moving coil galvanometer is wound over a metal frame in order to ______.
The current sensitivity of a galvanometer increase by 20%. If its resistance also increases by 25%, the voltage sensitivity will ______.
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 an ammeter 0.5% of main current passes through galvanometer; If resistance of galvanometer is G, the resistance of ammeter will be.
Explain in brief the basic construction of a moving-coil table galvanometer whit a neat labelled diagram.
A resistance of 3Ω is connected in parallel to a galvanometer of resistance 297Ω. Find the fraction of current passing through the galvanometer.
