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प्रश्न
To convert a moving coil galvanometer into an ammeter we need to connect a ______.
पर्याय
small resistance in parallel with it
large resistance in series with it
small resistance in series with it
large resistance in parallel with it
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उत्तर
To convert a moving coil galvanometer into an ammeter we need to connect a small resistance in parallel with it.
Explanation:
To turn a moving coil galvanometer into an ammeter, a low-resistance, known as a shunt, is connected parallel to the galvanometer. The shunt allows the majority of the current to bypass the galvanometer, allowing it to measure high currents without being harmed. This ensures that the galvanometer deflection is proportional to the total current in the circuit.
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संबंधित प्रश्न
The combined resistance of a galvanometer of resistance 500Ω and its shunt is 21Ω. Calculate the value of shunt.
Show that the current flowing through a moving coil galvanometer is directly proportional to the angle of deflection of coil.
Write the underlying principle of a moving coil galvanometer.
Why does a galvanometer show a momentary deflection at the time of charging or discharging a capacitor? Write the necessary expression to explain this observation.
A circular coil of 250 turns and diameter 18 cm carries a current of 12A. What is the magnitude of magnetic moment associated with the coil?
Why is it necessary to introduce a cylindrical soft iron core inside the coil of a galvanometer?
Increasing the current sensitivity of a galvanometer may not necessarily increase its voltage sensitivity. Explain, giving reason.
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.
- A circular coil of 30 turns and radius 8.0 cm carrying a current of 6.0 A is suspended vertically in a uniform horizontal magnetic field of magnitude 1.0 T. The field lines make an angle of 60° with the normal of the coil. Calculate the magnitude of the counter torque that must be applied to prevent the coil from turning.
- Would your answer change, if the circular coil in (a) were replaced by a planar coil of some irregular shape that encloses the same area? (All other particulars are also unaltered.)
Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.
A moving coil galvanometer has a resistance of 25Ω and gives a full scale deflection for a current of 10mA. How will you convert it into a voltmeter having range 0 - 100 V?
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?
Why is it necessary to introduce a radial magnetic field inside the coil of a galvanometer?
How will you convert a moving coil galvanometer into a voltmeter?
With the help of a neat and labelled diagram, explain the principle and working of a moving coil galvanometer ?
Define the current sensitivity of a galvanometer ?
In the meter bridge experiment, balance point was observed at J with AJ = l.
(i) The values of R and X were doubled and then interchanged. What would be the new position of balance point?
(ii) If the galvanometer and battery are interchanged at the balance position, how will the alance point get affected?
State the principle of the working of a moving coil galvanometer, giving its labeled diagram ?
State the underlying principle of working of a moving coil galvanometer. Write two reasons why a galvanometer can not be used as such to measure current in a given circuit. Name any two factors on which the current sensitivity of a galvanometer depends.
A coil of radius 10 cm and resistance 40 Ω has 1000 turns. It is placed with its plane vertical and its axis parallel to the magnetic meridian. The coil is connected to a galvanometer and is rotated about the vertical diameter through an angle of 180°. Find the charge which flows through the galvanometer if the horizontal component of the earth's magnetic field is BH = 3.0 × 10−5 T.
Define the term ‘current sensitivity’ of a moving coil galvanometer.
A galvanometer coil has a resistance of 12 Ω and the metre shows full scale deflection for a current of 3 mA. How will you convert the metre into a voltmeter of range 0 to 18 V?
A galvanometer coil has a resistance of 15 Ω and the metre shows full scale deflection for a current of 4 mA. How will you convert the metre into an ammeter of range 0 to 6 A?
The current sensitivity of a galvanometer is defined as ______.
In a moving coil galvanometer the deflection (Φ) on the scale by a pointer attached to the spring is ______.
The conversion of a moving coil galvanometer into a voltmeter is done by ______.
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:
A galvanometer of resistance 100 Ω gives a full-scale deflection for a current of 10−5 A. To convert it into an ammeter capable of measuring up to 1 A we should connect a resistance of ______.
In an ammeter 0.5% of main current passes through galvanometer; If resistance of galvanometer is G, the resistance of ammeter will be.
When a galvanometer is shunted with a 4 Ω resistance, the deflection is reduced to one-fifth. If the galvanometer is further shunted with a 2 Ω wire. The further reduction (find the ratio of decrease in current to the previous current) in the deflection will be (the main current remains the same)
A galvanometer having a resistance of 20 Ω and 30 Ω division on both sides has figure of merit 0.005 ampere/division. The resistance that should be connected in series such that it can be used as a voltmeter upto 15 volt, is ______.
A galvanometer of resistance 100 Ω gives a full-scale deflection for a potential difference of 200 mV.
- What must be the resistance connected to convert the galvanometer into an ammeter of the range 0-200 mA?
- Determine resistance of the ammeter.
A sensitive electromagnetic instrument used to detect and measure small electric currents (of the order of microamperes to milliamperes) by measuring the deflection of a current-carrying coil placed in a uniform magnetic field is called a:
The unit in which the current sensitivity of a galvanometer is expressed is:
The voltage sensitivity of a moving coil galvanometer, where G is the resistance of the galvanometer coil, is given by:
Between two galvanometers, the one with the smaller figure of merit is:
When a current-carrying coil of N turns and area A, carrying current I, is placed in a magnetic field B, the magnitude of the magnetic torque acting on it is:
The equilibrium condition \(NIAB = C\phi\) leads to the current–deflection relationship:
In a suspended-coil galvanometer, the phosphor-bronze strip serves to:
In the pivoted-coil (Weston) type galvanometer, the two hair springs:
The pointer used to read the deflection on the calibrated scale of a moving coil galvanometer is made of:
The non-magnetic frame of a moving coil galvanometer is made of aluminium, and its function is to provide:
An ammeter, ideally, has:
In a circuit with a 3 V source and a 3 Ω resistor, the galvanometer \((R_G = 60\ \Omega)\) is converted into an ammeter using a shunt resistance \(r_s = 0.02\ \Omega\). The measured current is approximately:
