RC time constant = Resistance × Capacitance
Put in the dimensions of each part: [ML²T⁻³A⁻²] × [M⁻¹L⁻²T⁴A²] = [T].
The SI unit of rc time constant is second (s).
These quantities have exactly the same dimensions, a favourite trick in JEE and NEET "which pair has the same dimensions" questions:
Can you get today's formula in one try?Play MLT, the free daily dimensional formula game| Quantity | Formula |
|---|---|
| Electric resistance | [M L2 T−3 A−2] |
| Electrical conductance | [M−1 L−2 T3 A2] |
| Resistivity | [M L3 T−3 A−2] |
| Current density | [L−2 A] |
| Electromotive force | [M L2 T−3 A−1] |
| Electric power | [M L2 T−3] |
| Electrical conductivity | [M−1 L−3 T3 A2] |
| Mobility | [M−1 T2 A] |
| Electrochemical equivalent | [M T−1 A−1] |