1Which of these has the same dimensions as electric potential?
Electric potential and potential difference both have the dimensions [M L² T⁻³ A⁻¹].
ElectrostaticsClass 12, Electrostatic Potential and Capacitance
Dimensional formula of Electric potential
[M L2 T-3 A-1]
Energy per unit charge. Potential difference, voltage and emf all share this dimension.
How to get the dimensional formula of electric potential
- Start from the definition: electric potential = energy / electric charge.
- velocity = length / time, so velocity is [L] / [T] = [L T-1].
- energy = mass × velocity2, so energy is [M] × [L T-1]2 = [M L2 T-2].
- electric charge = electric current × time, so electric charge is [A] × [T] = [T A].
- Put in the dimension of each part: [M L2 T-2] / [T A].
- Add the powers of each base quantity: [M L2 T-3 A-1].
Quantities with the dimensions [M L² T⁻³ A⁻¹]
Equal dimensions do not make them the same quantity. Compare electric potential with the others in the full grid.
Three questions on electric potential
2What is the SI unit of electric potential?
The SI unit of electric potential is the volt (V).
3Which one has different dimensions from the others?
Capacitance is [M⁻¹ L⁻² T⁴ A²]. The other three are all [M L² T⁻³ A⁻¹].
An equation that uses electric potential
Equation checker
Matching dimensions are necessary, not sufficient. A check cannot see pure numbers such as 1/2 or 2π, so a consistent equation can still be wrong.
Read as
E = (1/2) C V2E[M L2 T-2]=1/2 C V2[M L2 T-2]Dimensionally consistentEvery term is [M L2 T-2]
Electric potential: quick answers
What is the dimensional formula of electric potential?
The dimensional formula of electric potential is [M L² T⁻³ A⁻¹]. It comes from electric potential = energy / electric charge.
What is the SI unit of electric potential?
The SI unit of electric potential is the volt (V).
Which quantities have the same dimensions as electric potential?
Electric potential shares [M L² T⁻³ A⁻¹] with potential difference, electromotive force (emf), stopping potential. Equal dimensions do not make them the same quantity.