Question

The SI unit of resistance is :
(A) Newton
(B) Ohm
(C) Watt
(D) Joule

Answer 1

Hint Resistance is measured in ohm \[\left( \Omega \right)\] . It is so-called after the German physicist Georg Simon Ohm. Mathematically, it is the ratio of the potential difference $\left( V \right)$ applied across the resistor to the current $\left( I \right)$ flowing through it.

Complete Step-by-step answer
Electric current is mainly the flow of electrons through the conductor. The flow of electrons is due to the potential difference at the ends of the conductor. This stream of electrons encounters resistance as soon as it starts moving within the body.
Electric current flowing through the conductor, the potential difference and the resistance of the conductor or wire is correlated as
$R = \dfrac{V}{I}$
The resistance of a resistor is measured in ohm $\left( \Omega \right)$, which is the SI unit.
The resistance of a wire is $1$ ohm, meaning that for a current of $1$ Ampere to flow through the wire, $1$ Volt of potential difference is required. Or, when the potential difference across the ends of the wire is 1 volt, then a current of $1$ Ampere flows through it.
It has been named after the German physicist, Georg Simon Ohm.

Therefore, the correct option is (B) Ohm.

Additional information
The S.I unit of force is Newton and it is first discovered by scientist Isaac Newton so the S.I. The unit is named after him, which is Newton.
The S.I unit of power is watt. It is named after James Watt.
The S.I unit of energy is joule while the CGS unit of energy is erg.
The electrical resistance of an object due to the arrangement of atoms in the crystal structure. As the atoms vibrate, they strike and pose a hindrance to the free flow of electrons. This is also the cause of why resistance rises with temperature in metals. With temperature rise, the atoms gain more thermal energy and vibrate even more vigorously, thus causing more of a hindrance to the free flow of electrons and hence electric current.

Note The SI system of units is the most commonly accepted system of units of measurement. They are used all over the world and are considered to be the official metric of units for all scientific purposes. Then, a student must be thorough with all the SI units of the physical quantities. They should also be thoroughgoing with the dimensions of the physical quantities.