Why is Wheatstone's bridge more accurate?

Wheatstone’s bridge refers to an arrangement of 4 resistances in order to measure one of them in terms of the other three resistances. A Wheatstone Bridge is more accurate than other methods to measure resistance as in the Wheatstone bridge, the resistance is obtained using the null method which is based on Kirchhoff’s law.

  • In the null method, the resistance of galvanometer and internal resistance of the cell doesn’t affect the null point.
  • If one or more out of the four resistances are changed, the current passing through the galvanometer becomes zero. This point is known as the null point.
  • Under this condition, the Wheatstone bridge is balanced.

Related Questions

  1. Meter Bridge or Slide Wire Bridge is a practical form of?
  2. Why Carey Foster Bridge Is So Sensitive?
  3. Can you find very high resistance accurately with the help of a Metre bridge?
  4. Meter bridge works on the principle of?
  5. How do you solve an unbalanced bridge?
  6. Why should we get the null point in the middle of the Metre bridge wire?
  7. What Is Null Voltage?

Read More:

CBSE CLASS XII Related Questions

  • 1.
    A current of \(4.0\,\text{A}\) flows through a wire of length \(1\,\text{m}\) and cross-sectional area \(1.0\,\text{mm}^2\), when a potential difference of \(2\,\text{V}\) is applied across its ends. Calculate the resistivity of the material of the wire.


      • 2.
        Two point charges -Q and Q are located at points (d, 0) and (0, d) respectively, in x-y plane. The electric field E at the origin will be:

          • \(\frac{1}{4\pi\epsilon_0} \frac{\sqrt{2}Q}{d^2} (\hat{i} - \hat{j})\)
          • \(\frac{1}{4\pi\epsilon_0} \frac{\sqrt{2}Q}{d^2} (-\hat{i} - \hat{j})\)
          • \(\frac{1}{4\pi\epsilon_0} \frac{Q}{d^2} (\hat{i} - \hat{j})\)
          • \(\frac{1}{4\pi\epsilon_0} \frac{Q}{d^2} (-\hat{i} - \hat{j})\)

        • 3.

          A ray of light MN is incident normally on the face corresponding with side AB of a prism with an isosceles right-angled triangular base ABC. Trace the path of the ray as it passes through the prism when the refractive index of the prism material is (i) $\sqrt{2}$, and (ii) $\sqrt{3}$.


            • 4.

              An electron is revolving around a proton in a circular orbit of radius $r$. Using classical physics, prove that the ratio of value of the angular momentum and the value of magnetic moment of electron revolving in the orbit is a constant.


                • 5.
                  A wire of length \(L\) is bent round into (i) a square coil having \(N\) turns and (ii) a circular coil having \(N\) turns. The coil in both cases is free to turn about a vertical axis coinciding with the plane of the coil, in a uniform, horizontal magnetic field and carry the same currents. Find the ratio of the maximum value of the torque acting on the square coil to that on the circular coil.


                    • 6.

                      The number of free electrons per unit volume ($\text{m}^3$) in a wire made of copper (resistivity $1.72 \times 10^{-8}\,\Omega\,\text{m}$) is $8.5 \times 10^{28}$. Calculate the average number of collisions made by an electron in one second when an electric field is maintained in the wire.

                        CBSE CLASS XII Previous Year Papers

                        Comments


                        No Comments To Show