Question

The unit of work is joule in the s.i system and erg in the cgs system.find number of ergs in 1 joule

Answer 1

1 joule = 10^7 ergs.

Answer 2

Question :

• The unit of work is joule in the SI system and erg in the CGS system. Find number of ergs in 1 joule

To Find :

• number of ergs in 1 joule energy

Solution :

$\tt Energy = mass \times {(velocity)}^{2} \\ \\ \tt energy= mass \times { \bigg( \frac{length}{time} \bigg) }^{2} = M {L}^{2} {T}^{ - 2} \\ \\ \tt 1 \: joule = (1kg)(1 {m})^{2} (1 {s)}^{ - 2} \\ \\ \tt 1 erg = (1g)( {1cm)}^{2} (1 {s)}^{ - 2} \\ \\ \tt \dfrac{1 joule}{1 \: erg} = \bigg(\dfrac{1kg}{1g} \bigg) \bigg( { \frac{1m}{1cm} \bigg) }^{2} \bigg( { \frac{1s}{1s} \bigg) }^{ - 2} \\ \\ \tt \implies \bigg( \frac{1000g}{1g} \bigg) \bigg( { \frac{100cm}{1cm} \bigg) }^{2} \\ \\ \tt\implies 1000 \times 10000 \\ \\ \tt\implies {10}^{7}$

$\boxed{ \bf \blue{1 \: joule = {10}^{7} erg}}$