Advertisements
Advertisements
Question
A wire has a length of 2.0 m and a resistance of 5.0 Ω. Find the electric field existing inside the wire if it carries a current of 10 A.
Advertisements
Solution
Given:-
Length of the wire, l = 2 m
Resistance of the wire, R = 5 Ω
Current through the wire, i = 10 A
From Ohm's Law, the potential difference across the wire,
V = iR
∴ V= 10 × 5 = 50 V
Electric field,
\[E = \frac{V}{l}\]
\[ = \frac{50}{2}\]
\[ = 25 V/m\]
APPEARS IN
RELATED QUESTIONS
A low voltage supply from which one needs high currents must have very low internal resistance. Why?
Name the unit of electrical resistance and give its symbol.
How should the two resistances of 2 ohms each be connected so as to produce an equivalent resistance of 1 ohm?
Calculate the current flowing through a wire of resistance 5 Ω connected to a battery of potential difference 3 V.
In an experiment of verification of Ohm’s law following observations are obtained.
|
Potential difference V (in volt) |
0.5 | 1.0 | 1.5 | 2.0 | 2.5 |
| current I (in ampere) | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 |
Draw a V-I graph and use this graph to find:
- the potential difference V when the current I is 0.5 A,
- the current I when the potential difference V is 0.75 V,
- the resistance in a circuit.
How would you connect two resistors in series? Draw a diagram. Calculate the total equivalent resistance.
Show by a diagram how two resistors R1 and R2 are joined in parallel. Obtain an expression for the total resistance of the combination.
In the circuit shown below in Fig, calculate the value of x if the equivalent resistance between A and B is 4 Ω.
Fig. represents the circuit used for the verification of ohm's law. Label the different parts from A and F. State the function of each.
Rewrite the following statement by selecting the correct option.
The S.I. unit of resistance is __________.
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.
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
The slope of voltage (V) versus current (I) is called:
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 hue?
Consider a current carrying wire (current I) in the shape of a circle. Note that as the current progresses along the wire, the direction of j (current density) changes in an exact manner, while the current I remain unaffected. The agent that is essentially responsible for is ______.
Let the resistance of an electrical device remain constant, while the potential difference across its two ends decreases to one fourth of its initial value. What change will occur in the current through it? State the law which helps us in solving the above stated question.
The resistance of a resistor is reduced to half of its initial value. If other parameters of the electrical circuit remain unaltered, the amount of heat produced in the resistor will become ______.
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.
