A 5-A fuse wire can withstand a maximum power of 1W incircuit.The resistance of the fuse wire is:
A 5-A fuse wire can withstand a maximum power of 1W incircuit.The resistance of the fuse wire is:
0.02 Ω
0.2 Ω
0.4 Ω
0.04 Ω
The Correct Option is D
Solution and Explanation
Given: 1 W of power, 5 I of current A resistance (R)
The rate at which energy flows through a resistor determines its power. The limiting energy flow after which the resistor (or wire in this case) would fuse is maximum power.
We are aware of this because P=I2RR= I2 P=25A2 1W=0.04
Top Questions on Current electricity
- Calculate the value of the current passing through the battery in the given circuit diagram.
- CBSE CLASS XII - 2025
- Physics
- Current electricity
- The equivalent resistance between points A and B in a circuit with two resistors of 6 \(\Omega\) each connected in parallel is:
- BITSAT - 2025
- Physics
- Current electricity
A battery of emf \( E \) and internal resistance \( r \) is connected to a rheostat. When a current of 2A is drawn from the battery, the potential difference across the rheostat is 5V. The potential difference becomes 4V when a current of 4A is drawn from the battery. Calculate the value of \( E \) and \( r \).
- CBSE CLASS XII - 2025
- Physics
- Current electricity
- In the given figure, three identical bulbs P, Q, and S are connected to a battery.
[(i)] Compare the brightness of bulbs P and Q with that of bulb S when key K is closed.
[(ii)] Compare the brightness of the bulbs S and Q when the key K is opened.
Justify your answer in both cases.
- CBSE CLASS XII - 2025
- Physics
- Current electricity
- Two conductors A and B of the same material have their lengths in the ratio 1:2 and radii in the ratio 2:3. If they are connected in parallel across a battery, the ratio \( \frac{v_A}{v_B} \) of the drift velocities of electrons in them will be:
- CBSE CLASS XII - 2025
- Physics
- Current electricity
Questions Asked in NEET exam
- A microscope has an objective of focal length \(f_o = 2\) cm and an eyepiece of focal length \(f_e = 4\) cm. The tube length of the microscope is \(L = 40\) cm. If the distance of distinct vision of eye is \(D = 25\) cm, the magnification in the microscope is:
- NEET (UG) - 2025
- Optical Instruments
- Which one of the following is an example of ex-situ conservation?
- NEET (UG) - 2025
- Ex-Situ Conservation
- Which one of the following compounds can exist as cis-trans isomers?
- NEET (UG) - 2025
- Organic Chemistry
- Who proposed that the genetic code for amino acids should be made up of three nucleotides?
- NEET (UG) - 2025
- Molecular Biology
- An electron (mass \(9 \times 10^{-31}\) kg and charge \(1.6 \times 10^{-19}\) C) moving with speed \(c/100\) (\(c\) = speed of light) is injected into a magnetic field of magnitude \(9 \times 10^{-4}\) T perpendicular to its direction of motion. We wish to apply a uniform electric field \( \vec{E} \) together with the magnetic field so that the electron does not deflect from its path. (speed of light \(c = 3 \times 10^8\) m/s):
- NEET (UG) - 2025
- Electric Field
Concepts Used:
Electric Current
Defining Electric Current
It is the rate of flow of electrons in a conductor. SI Unit - Ampere (A).
Electrons are negatively charged particles hence when they move a number of charges moves.
Note:- The ability of a particular substance to conduct electricity depends on the number of electrons that are able to move . Some of the materials allow current to flow better than others.
What is an Electromotive Force?
If a force acts on electrons to make them move in a particular direction, then up to some extent random motion of the electrons will be eliminated. An overall movement in one direction. The force which acts on the electrons to move them in a certain direction is known as electromotive force and its quantity is known as voltage and is measured in V.