Question

Express the power of a 100 watt bulb in CGS unit.

Answer 1

In SI unit, watt = joule/s
In CGS unit, 1 joule = 10⁷ erg
So, 100 watt = 100 joule/s $=\frac{100\times {10}^7\mathrm{erg}}{1\mathrm{s}}={10}^9\mathrm{erg}/\mathrm{s}$