Question
Draw a circuit diagram using a metre bridge and write the necessary mathematical relation used to determine the value of an unknown resistance. Why cannot such an arrangement be used for measuring very low resistances?
✓
Answer
$\text{R} = \frac{\ell_{1}}{\big(100 - \ell_{1}\big)}$End correction can be comparable with the low resistance used or unknown contact resistance (strips of connecting wires) becomes comparable with low resistance to be measured.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Is the magnification equal to the magnifying power in this case? Explain.
The decay constant of $\text{ }^{197}_{80}\text{Hg} \ ($electron capture to $\text{ }^{197}_{79}\text{Au})$ is $1.8 \times 10^{-4} S^{-1}$.
→- What is the half $-$ life?
- What is the average $-$ life?
- How much time will it take to convert $25\%$ of this isotope of mercury into gold?
The pressures of the gas in a constant volume gas thermometer are 80cm, 90cm and 100cm of mercury at the ice point, the steam point and in a heated wax bath, respectively. Find the temperature of the wax bath.
The angles of dip at two places located on the earth are 0° and 90° respectively. Where are the places located?
A point charge is taken from a point A to a point B in an electric field. Does the work done by the electric field depend on the path of the charge?
The outer surface of a cylinder containing a gas is rubbed vigorously by a polishing machine. The cylinder and its gas become warm. Is the energy transferred to the gas heat or work?
What is resistivity ? On What factors does it depend and write its unit and dimensional formula.
The speed of sound as measured by a student in the laboratory on a winter day is $340m/s$ when the room temperature is $17^\circ\ C.$ What speed will be measured by another student repeating the experiment on a day when the room temperature is $32^\circ\ C$?
→Draw a plot of the binding energy per nucleon as a function of mass number for a large number of nuclei, 2⩽ A⩽240. How do you explain the constancy of binding energy per nucleon in the range 30 < A < 170 using the property that nuclear force is short - ranged?
Explain the structure of Polaroid.