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प्रश्न
Ohm's law gives a relationship between:
(a) current and resistance
(b) resistance and potential difference
(c) potential difference and electric charge
(d) current and potential difference
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उत्तर
(d) current and potential difference
Ohm's law gives the relationship between current and potential difference.
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संबंधित प्रश्न
Find the resistance of a conductor if 0.24 A current is passing through it and a potential difference of 24 V is applied across it.
Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?
Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Calculate the value of the resistance of the resistor.
How should the two resistances of 2 ohms each be connected so as to produce an equivalent resistance of 1 ohm?
A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination of resistances in half a minute.
A car bulb connected to a 12 volt battery draws 2 A current when glowing. What is the resistance of the filament of the bulb? Will the resistance be more same or less when the bulb is not glowing?
How does an increase in the temperature affect the specific resistance of a :
(i) Metal and
(ii) Semiconductor ?
Tick(✓) the correct choice in the following:
Ohm's law is applicable to
- Name and state the law which relates the potential difference and current in a conductor.
- What is the necessary condition for a conductor to obey the law named above in part (a) ?
State the relation correlating the electric current flowing in a conductor and the voltage applied across it. Also, draw a graph to show this. relationship.
The variable resistance is called ____________.
The heat produced by a 100 w heater in 2 minute is equal to
A metal rod of length 10 cm and a rectangular cross-section of 1 cm × `1/2` cm is connected to a battery across opposite faces. The resistance will be ______.
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?
How is electric current related to the potential difference across the terminals of a conductor?
Draw a labelled circuit diagram to verify this relationship.
The voltage - current readings of a certain material are shown in the table given below:
| Voltage (V) | 10 V | 20 V | 30 V |
| Current (I) | 2 A | 3 A | 4 A |
Study the table.
- State whether the conductor used is ohmic or non-ohmic.
- Justify your answer.
- State Ohm's law.
The circuit depicted in the figure is employed for studying Ohm’s Law. Instead of using a standard resistor, a student opts for a glass tube filled with mercury (tube 1), connected to the circuit through two electrodes, E1 and E2. He records the readings of the ammeter and voltmeter, thereby calculating the resistance. The student repeats the experiment by substituting tube 1 with tube 2, where the same amount of mercury fills tube 2.
Neglecting internal resistance of the cell use (> or < or =) to compare:
- the resistance in both the cases.
- the voltmeter readings in both the cases.
- the specific resistance in both the cases.
