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प्रश्न
What is the SI unit of potential gradient?
उत्तर
SI unit of the potential gradient is volt/metre.
APPEARS IN
संबंधित प्रश्न
(i) State the principle on which a potentiometer works. How can a given potentiometer be made more sensitive?
In the given circuit in the steady state, obtain the expressions for (a) the potential drop (b) the charge and (c) the energy stored in the capacitor, C.
State the working principle of a potentiometer. With the help of the circuit diagram, explain how a potentiometer is used to compare the emf's of two primary cells. Obtain the required expression used for comparing the emfs.
Would you prefer a voltmeter or a potentiometer to measure the emf of a battery?
The potentiometer wire AB shown in the figure is 40 cm long. Where should the free end of the galvanometer be connected on AB, so that the galvanometer may show zero deflection?
In a potentiometer experiment, the balancing length with a resistance of 2Ω is found to be 100 cm, while that of an unknown resistance is 500 cm. Calculate the value of the unknown resistance.
Figure below shows two resistors R1 and R2 connected to a battery having an emf of 40V and negligible internal resistance. A voltmeter having a resistance of. 300 Ω is used to measure the potential difference across R1 Find the reading of the voltmeter.
Draw a labelled circuit diagram of a potentiometer to compare emfs of two cells. Write the working formula (Derivation not required).
A student uses the circuit diagram of a potentiometer as shown in the figure
(a) for a steady current I passing through the potentiometer wire, he gets a null point for the cell ε1. and not for ε2. Give the reason for this observation and suggest how this difficulty can be resolved.
(b) What is the function of resistance R used in the circuit? How will the change in its value affect the null point?
(c) How can the sensitivity of the potentiometer be increased?
Define potential gradient of the potentiometer wire.
Why should not the jockey be slided along the potentiometer wire?
State the uses of a potentiometer.
What are the disadvantages of a potentiometer?
Distinguish between a potentiometer and a voltmeter.
Describe how a potentiometer is used to compare the EMFs of two cells by connecting the cells individually.
Describe with the help of a neat circuit diagram how you will determine the internal resistance of a cell by using a potentiometer. Derive the necessary formula.
Describe how a potentiometer is used to compare the emf's of two cells by the combination method.
The SI unit of the potential gradient is ______
If the potential gradient of a wire decreases, then its length ______
State any one use of a potentiometer.
The emf of a standard cell is 1.5V and is balanced by a length of 300 cm of a potentiometer with a 10 m long wire. Find the percentage error in a voltmeter that balances at 350 cm when its reading is 1.8 V.
Which of the following instruments is not a direct reading instrument?
A potentiometer wire is 4m long and potential difference of 3V is maintained between the ends. The emf of the cell, which balances against a length of 100 cm of the potentiometer wire is ____________.
A 10 m long wire of resistance 20 Q is connected in series with a battery of emf 3 V and a resistance of 10 Ω. The potential gradient along the wire in V/m is ________.
The resistance of the potentiometer wire should ideally be ____________.
In a potentiometer experiment, when the galvanometer shows no deflection, then no current flows through ____________.
The potentiometer is more sensitive, when ______.
A potentiometer wire has length L For given cell of emf E, the balancing length is `"L"/3` from 3 the positive end of the wire. If the length of the potentiometer wire is increased by 50%, then for the same cell, the balance point is obtained at length.
A potentiometer wire of Length 10 m is connected in series with a battery. The e.m.f. of a cell balances against 250 cm Length of wire. If length of potentiometer wire is increased by 1 m, the new balancing length of wire will be ____________.
Which of the following is true for a potentiometer?
To determine the internal resistance of a cell by using potentiometer, the null point is at 1 m when cell is shunted by 3 Ω resistance and at a length 1.5 m when cell is shunted by 6 Ω resistance. The internal resistance of the cell is ______.
The length of a wire of a potentiometer is 100 cm, and the e.m.f of its standard cell is E volt. It is employed to measure the e.m.f of a battery whose internal resistance is 0.5 `Omega` If the balance point is obtained at `l`= 30 cm from the positive end, the e.m.f of the battery is ____________.
where 'i' is the current in the potentiometer
A wire has a length of 2m and a resistance of 10Ω. It is connected in series with a resistance of 990Ω and a cell of e.m.f. 2V. The potential gradient along the wire will be ______
A potentiometer wire is 4 m long and a potential difference of 3 V is maintained between the ends. The e.m.f. of the cell which balances against a length of 100 cm of the potentiometer wire is ______
A potentiometer wire of length 'L' and a resistance 'r' are connected in series with a battery of E.M.F. 'E0' and a resistance 'r1'. A cell of unknown E.M.F, 'E' is balanced at a length 'ℓ' of the potentiometer wire. The unknown E.M.F. E is given by ______
In the potentiometer experiment, cells of e.m.f. E1 and E2 are connected in series (E1 > E2). the balancing length is 64 cm of the wire. If the polarity of E2 is reversed, the balancing length becomes 32 cm. The ratio `E_1/E_2` is ______
In a potentiometer experiment, for measuring internal resistance of a cell, the balance point has been obtained on the fourth wire. The balance point can be shifted to fifth wire by ______.
A battery is connected with a potentiometer wire. The internal resistance of the battery is negligible. If the length of the potentiometer wire of the same material and radius is doubled then ______.
In a potentiometer of 10 wires, the balance point is obtained on the 7th wire. To shift the balance point to 9th wire, we should ______.
AB is a wire of potentiometer with the increase in value of resistance R, the shift in the balance point J will be:
Three resistance each of 4Ω are connected to from a triangle. The resistance b / w two terminal is
Specific resistance of a conductor increase with.
Consider a simple circuit shown in figure 
stands for a variable resistance R′. R′ can vary from R0 to infinity. r is internal resistance of the battery (r << R << R0).
- Potential drop across AB is nearly constant as R ′ is varied.
- Current through R′ is nearly a constant as R ′ is varied.
- Current I depends sensitively on R′.
- `I ≥ V/(r + R)` always.
While doing an experiment with potentiometer (Figure) it was found that the deflection is one sided and (i) the deflection decreased while moving from one end A of the wire to the end B; (ii) the deflection increased. while the jockey was moved towards the end B.
- Which terminal + or – ve of the cell E1, is connected at X in case (i) and how is E1 related to E?
- Which terminal of the cell E1 is connected at X in case (ii)?
In balanced meter bridge, the resistance of bridge wire is 0.1 Ω cm. Unknown resistance X is connected in left gap and 6 Ω in right gap, null point divides the wire in the ratio 2:3. Find the current drawn from the battery of 5 V having negligible resistance.
A potentiometer wire AB having length L and resistance 12r is joined to a cell D of emf ε and internal resistance r. A cell C having emt `ε/2` and internal resistance 3r is connected. The length AJ at which the galvanometer as shown in the figure shows no deflection is ______.
What is the value of resistance for an ideal voltmeter?
The emf of the cell of internal resistance 1.275 Ω balances against a length of 217 cm of a potentiometer wire. Find the balancing length when the cell is shunted by a resistance of 15 Ω.
