Advertisements
Advertisements
प्रश्न
Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?
Will current flow more easily through a thick wire or a thin wire of the same material when connected to the same source? Give reason for your answer.
Advertisements
उत्तर १
The current will flow more easily through thick wire. It is because the resistance of a
conductor is inversely proportional to its area of cross-section. If thicker the wire, less is resistance and hence more easily the current flows.
उत्तर २
Resistance (R) is inversely proportional to the area of the cross-section (A) of the
wire. So, thicker the wire, lower is the resistance of the wire and vice-versa.
Therefore, current can flow more easily through a thick wire than a thin wire.
`R = rho xx l/A`
`R ∝ 1/A`
उत्तर ३
The resistance of a conductor is inversely proportional to its area of cross-section, i.e. `R ∝ 1/A`. So as the conductor is a thick wire, its resistance decreases and current will flow easily through it, in comparison with a thin wire.
APPEARS IN
संबंधित प्रश्न
What will be the change in the current if the potential difference is kept constant and the resistance of the circuit is made four times?
- It will remain unchanged.
- It will become four times.
- It will become one-fourth.
- It will become half.
Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
Name the law which is illustrated by the above V−I graph.
Keeping the p.d. constant, the resistance of a circuit is halved. The current will become:
(a) one-fourth
(b) four time
(c) half
(d) double
The graph between V and I for a conductor is a straight line passing through the origin.
Which law is illustrated by such a graph?
How does an increase in the temperature affect the specific resistance of a :
(i) Metal and
(ii) Semiconductor ?
State and define Ohm’s law.
Draw a neat diagram for the verification of Ohm’s law by voltmeter-ammeter method. By another diagram show the relation between p.d. and current.
The ratio of the potential difference to the current is known as ________.
A wire connected to a power supply of 230 V has power dissipation P1. Suppose the wire is cut into two equal pieces and connected parallel to the same power supply. In this case, power dissipation is P2. The ratio of `"P"_2/"P"_1` is
State macroscopic form of Ohm’s law.
Which of the following is correct for V-I graph of a good conductor?
The temperature of a conductor is increased. The graph best showing the variation of its resistance is:
A student carries out an experiment and plots the V-I graph of three samples of nichrome wire with resistances R1, R2 and R3 respectively. Which of the following is true?

Suppose there is a circuit consisting of only resistances and batteries and we have to double (or increase it to n-times) all voltages and all resistances. Show that currents are unaltered. Do this for circuit of Example 3.7 in the NCERT Text Book for Class XII.
What is the resistance of a conductor through which a current of 0.5 A flows when a potential difference of 2V is applied across its ends?
You are provided with a resistor, a key, an ammeter, a voltmeter, four cells of 1.5 V each and few connecting wires. Using circuit components, draw a labelled circuit diagram to show the setup to study Ohm's law.
State the relationship between potential difference (V) across the resistor and the current (I) flowing through it. Also draw V-I graph, taking V on the X-axis.
Why should an ammeter have low resistance?

Vinita and Ahmed demonstrated a circuit that operates the two headlights and the two sidelights of a car, in their school exhibition. Based on their demonstrated circuit, answer the following questions.
- State what happens when switch A is connected to:
a) Position 2
b) Position 3 - Find the potential difference across each lamp when lit.
- Calculate the current.
a) in each 12 Ω lamp when lit.
b) In each 4 Ω lamp when lit.
OR - Show, with calculations, which type of lamp, 4.0 Ω or 12 Ω, has the higher power.
