A milliammeter of range 10 mA has a coil of resistance $1\Omega$. To use it as a voltmeter of range 10 V, the resistance that must be connected in series with it is
- $999\,\Omega$
- $1000\,\Omega$
- $9\,\Omega$
- $99\,\Omega$
The Correct Option is A
Solution and Explanation
Top KCET Physics Questions
- The range of electrical conductivity \( \sigma \) and resistivity \( \rho \) for metals, among the following, is:
- KCET - 2025
- Physics
- Semiconductor electronics: materials, devices and simple circuits
- At 27°C temperature, the mean kinetic energy of the atoms of an ideal gas is \( E_1 \). If the temperature is increased to 327°C, then the mean kinetic energy of the atoms will be
- KCET - 2025
- Physics
- simple harmonic motion
- Two similar galvanometers are converted into an ammeter and a millammeter. The shunt resistance of ammeter as compared to the shunt resistance of millammeter will be
- KCET - 2025
- Physics
- Electrical Instruments
Charges are uniformly spread on the surface of a conducting sphere. The electric field from the center of the sphere in a point outside the sphere varies with distance \( r \) from the center as
- KCET - 2025
- Physics
- Electric Dipole
Match the following types of nuclei with examples shown:
- KCET - 2025
- Physics
- Nuclear physics
Top KCET Resistance Questions
The graph between variation of resistance of a wire as a function of its diameter keeping other parameters like length and temperature constant is
- KCET - 2025
- Physics
- Resistance
- The equivalent resistance between the points A and B in the following circuit is
- KCET - 2023
- Physics
- Resistance
- The four bands of a colour coded resistor are of the colours gray, red, gold and gold. The value of the resistance of the resistor is
- KCET - 2023
- Physics
- Resistance
- The resistance of a carbon resistor is 4.7 kΩ ± 5% . The colour of the third band is
- KCET - 2023
- Physics
- Resistance
- A wire of a certain material is stretched slowly by 10%. Its new resistance and specific resistance becomes respectively
- KCET - 2022
- Physics
- Resistance
Top KCET Questions
Match the following:
In the following, \( [x] \) denotes the greatest integer less than or equal to \( x \).
Choose the correct answer from the options given below:- KCET - 2025
- Differentiability
- If \[ y = \frac{\cos x}{1 + \sin x} \] then:
- KCET - 2025
- Differentiability
- A function \( f(x) \) is given by:
\[ f(x) = \begin{cases} \frac{1}{e^x - 1}, & \text{if } x \neq 0 \\ \frac{1}{e^x + 1}, & \text{if } x = 0 \end{cases} \] Then, which of the following is true?- KCET - 2025
- Limits
- The function f(x) is given by:
For x < 0:
f(x) = ex + axFor x ≥ 0:
f(x) = b(x - 1)2
The function is differentiable at x = 0. Then,- KCET - 2025
- Differentiability
- The derivative of \( \sin x \) with respect to \( \log x \) is:
- KCET - 2025
- Derivatives
Concepts Used:
Resistance
Resistance is the measure of opposition applied by any object to the flow of electric current. A resistor is an electronic constituent that is used in the circuit with the purpose of offering that specific amount of resistance.
R=V/I
In this case,
v = Voltage across its ends
I = Current flowing through it
All materials resist current flow to some degree. They fall into one of two broad categories:
- Conductors: Materials that offer very little resistance where electrons can move easily. Examples: silver, copper, gold and aluminum.
- Insulators: Materials that present high resistance and restrict the flow of electrons. Examples: Rubber, paper, glass, wood and plastic.
Resistance measurements are normally taken to indicate the condition of a component or a circuit.
- The higher the resistance, the lower the current flow. If abnormally high, one possible cause (among many) could be damaged conductors due to burning or corrosion. All conductors give off some degree of heat, so overheating is an issue often associated with resistance.
- The lower the resistance, the higher the current flow. Possible causes: insulators damaged by moisture or overheating.