How is Voltage related to Resistance?

The relationship between voltage and resistance is represented by Ohm's Law. It usually means that the flowing current passing via a circuit is directly proportional to the applied voltage and also inversely proportional to the resistance, with a condition that the temperature remains constant.

The relation between voltage and resistance can be expressed as:

Voltage

  1. Voltage is also referred to as Potential Difference.
  2. Potential Difference can be expressed as the work done in obtaining a unit positive charge from one point to another point in the same conductor.
  3. Volt (V) is the unit of potential difference.

Resistance

  1. When current passes or flows through a circuit, it undergoes a given resistive force.
  2. The parameter that usually represents the magnitude of this resistive force  is often called resistance.
  3. Ohm (Ω) is the unit of resistance.

What is Ohm's Law?

As per Ohm’s Law, the current that flows through a circuit is directly proportional to the voltage. Assume that:

  • V = Voltage
  • I = Current
  • R = Constant of Proportionality

Therefore,

V∝I

or, V = IR

Thus, this is how the relation between voltage and resistance can be expressed.


Read More Related Questions:

  1. How many 176 Ω resistors (in parallel) are required to carry 5 A on a 220 V line?
  2. Three identical cells, each of 4 V and internal resistance r, are connected in series to a 6 ohm resistor. If the current flowing in the circuit is 2 A. The internal resistance of each cell is?
  3. n identical light bulbs, each designed to draw P power from a certain voltage supply, are joined in series across that supply. The total power which they will draw is?
  4. Two bulbs are rated (P1, V) and (P2, V). If they are connected (i) in series and (ii) in parallel across a supply V Find the power dissipated in the two combinations in terms of P1 and P2.
  5. Why is the series arrangement not used for domestic circuits?
  6. Define: 1 volt, Potential difference
  7. Is resistance constant in Ohm's law?
  8. Find the current through a resistance 2 ohm if the voltage across the resistance is 6 V.
  9. What are the applications of ohm's law used in daily life?
  10. Why Do We Use Ohm's Law?
  11. Obtain the equation J = σE of Ohm's law on the basis of drift velocity
  12. What Is Effective Resistance?
  13. A small bulb has a resistance of 2 ohms when it is cold. It draws 0.4-ampere current from a source of4V and then starts glowing. Calculate the resistance when it is glowing

Also Read:

CBSE CLASS XII Related Questions

  • 1.
    Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.


      • 2.
        Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

          • The total charge of the two spheres is conserved.
          • Both spheres attain the same potential.
          • The final potential of the system equals $\frac{1}{4\pi\epsilon_0} \frac{(q_1 + q_2)}{(r_1 + r_2)}$
          • The final potential of the system equals $\frac{1}{4\pi\epsilon_0} \frac{(q_1 + q_2) (r_1 + r_2)}{r_1 r_2}$

        • 3.
          Read the following paragraph and answer the questions that follow.
          In an experiment with convex lens of focal length f, the screen is fixed at a distance D from the object. A student slowly moves the lens away from the object towards the screen and finds that she is able to form sharp image of the object for two positions of the lens. The distance between these two positions of the lens is d.


            • 4.
              Write two advantages of reflecting telescope over refracting telescope.


                • 5.
                  A charged particle $+q$ in an electric field $\vec{E}$ experiences a force in the direction of the electric field. As a result, its kinetic energy changes. Similarly, the charged particle also experiences a force when it moves in a magnetic field $\vec{B}$. But this magnetic force is perpendicular to both velocity $\vec{v}$ of the charged particle and the magnetic field $\vec{B}$, so it cannot change the kinetic energy of the charged particle. Consider two charged particles 1 and 2 of masses $m$ and $\frac{m}{2}$ having charges $-q$ and $+2q$ respectively. They are accelerated from rest through the same potential difference $V$ and acquire kinetic energy $K_1$ and $K_2$. Then they enter in a region of uniform magnetic field $\vec{B}$ perpendicular to their velocities.


                    • 6.
                      An electric field $\vec{E}$ is established across the ends of a cylindrical conductor of length L and area of cross-section A. Discuss how electrons attain an average velocity, independent of time. Hence, obtain a relation between current in the conductor and this ‘average velocity’ of electrons.

                        CBSE CLASS XII Previous Year Papers

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